Search references for ARCHIMEDEAN CIRCLE. Phrases containing ARCHIMEDEAN CIRCLE
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Circle in the arbelos congruent to the twin circles
geometry, an Archimedean circle is any circle constructed from an arbelos that has the same radius as each of Archimedes' twin circles. If the arbelos
Archimedean_circle
Spiral with constant distance from itself
The Archimedean spiral (also known as Archimedes' spiral, the arithmetic spiral) is a spiral named after the 3rd-century BC Greek mathematician Archimedes
Archimedean_spiral
Topics referred to by the same term
refer to: Archimedean absolute value Archimedean circle Archimedean constant Archimedean copula Archimedean field Archimedean group Archimedean point Archimedean
Archimedean
Circle constructed from an arbelos
Bankoff circle or Bankoff triplet circle is a certain Archimedean circle that can be constructed from an arbelos; an Archimedean circle is any circle with
Bankoff_circle
Simple curve of Euclidean geometry
A circle is a shape consisting of all points in a plane that are at a given distance from a given point, the centre. The distance between any point of
Circle
Archimedean circles constructed by Thomas Schoch
Schoch circles are twelve Archimedean circles constructed by Thomas Schoch. In 1979, Thomas Schoch discovered a dozen new Archimedean circles; he sent
Schoch_circles
Circles in two perpendicular families Circles of Apollonius – Several sets of circles associated with Apollonius of Perga Archimedean circle – Circle
List_of_circle_topics
Two congruent circles within an arbelos
circles congruent to the twin circles have also been found. These circles have also been called Archimedean circles. They include the Bankoff circle,
Twin_circles
Hydraulic machine
fountain. Archimedean spiral Screw-propelled vehicle Screw (simple machine) Spiral pump Toroidal propeller Vitruvius Also known as the Archimedean screw,[citation
Archimedes'_screw
Circles related to a point in the plane
two Archimedean circle, additional circles associated with and sometimes tangent to an arbelos Ring lemma, on the radii of a ring of tangent circles surrounding
Tangent_circles
Problem of constructing equal-area shapes
somehow already given, then a square and circle of equal areas can be constructed from it. The Archimedean spiral can be used for another similar construction
Squaring_the_circle
Perimeter of a circle or ellipse
circumferēns 'carrying around, circling') is the perimeter of a circle or ellipse. The circumference is the arc length of the circle, as if it were opened up
Circumference
Greek mathematician and physicist (c. 287 – 212 BC)
demonstrating that the area of a circle is proportional to its diameter was proven using a lemma now known as the Archimedean property, that “the excess by
Archimedes
below. Archimedean absolute value Archimedean circle Archimedean copula Archimedean group Archimedean ordered field Archimedean point Archimedean property
List of things named after Archimedes
List_of_things_named_after_Archimedes
Concept in geometry
area enclosed by a circle of radius r is πr2. Here, the Greek letter π represents the constant ratio of the circumference of any circle to its diameter,
Area_of_a_circle
In geometry, the Woo circles, introduced by Peter Y. Woo, are a set of infinitely many Archimedean circles. Form an arbelos with the two inner semicircles
Woo_circles
Topics referred to by the same term
(disambiguation) The Wizard of Oz (disambiguation) Woo circles, a set of infinitely many Archimedean circles Woo! Yeah!, a drum break Worcester, Massachusetts
Woo
Circle of immediate corresponding curvature of a curve at a point
An osculating circle is a circle that best approximates the curvature of a curve at a specific point. It is tangent to the curve at that point and has
Osculating_circle
1897 proposed law to define squaring the circle
whose perimeter is equal to the circumference of the circle. In the model circle above, the Archimedean area (accepting Goodwin's values for the circumference
Indiana_pi_bill
Ancient Greek mathematics book
around 225 BC. Notably, Archimedes employed the Archimedean spiral in this book to square the circle and trisect an angle. Archimedes begins On Spirals
On_Spirals
Four congruent circles associated with an arbelos
each have the same area as Archimedes' twin circles, making them Archimedean circles. An arbelos is formed from three collinear points A, B, and C, by
Archimedes'_quadruplets
Primitive way of calculating area
the method of exhaustion as a way to compute the area inside a circle by filling the circle with a sequence of polygons with an increasing number of sides
Method_of_exhaustion
congruent with Archimedes' twin circles, making it an Archimedean circle; it is one of the Schoch circles. The Schoch line is perpendicular to the line AC
Schoch_line
Curve that winds around a central point
consists of a sequence of circle arcs. The involute of a circle looks like an Archimedean, but is not: see Involute of a circle. The following considerations
Spiral
patterns, Branko Grünbaum calls the vertex-uniform tilings Archimedean, in parallel to the Archimedean solids. Their dual tilings are called Laves tilings in
List of Euclidean uniform tilings
List_of_Euclidean_uniform_tilings
Self-similar growth curve
Archimedean spiral in that the distances between the turnings of a logarithmic spiral increase in a geometric progression, whereas for an Archimedean
Logarithmic_spiral
Catalan solid with 120 faces
triacontahedron or d120 is a Catalan solid with 120 faces and the dual to the Archimedean truncated icosidodecahedron. As such it is face-uniform but with irregular
Disdyakis_triacontahedron
Polygonal curve made from right triangles
Spiral of Theodorus approximates the Archimedean spiral. Just as the distance between two windings of the Archimedean spiral equals mathematical constant
Spiral_of_Theodorus
Straight line segment that passes through the centre of a circle
a diameter of a circle is any straight line segment that passes through the centre of the circle and whose endpoints lie on the circle. It can also be
Diameter
Archimedean solid with 32 faces
each separating a triangle from a pentagon. As such, it is one of the Archimedean solids and more particularly, a quasiregular polyhedron. One way to construct
Icosidodecahedron
Overview of and topical guide to geometry
Pyramid Parallelepiped Tetrahedron Heronian tetrahedron Platonic solid Archimedean solid Kepler-Poinsot polyhedra Johnson solid Uniform polyhedron Polyhedral
Outline_of_geometry
Type of curvilinear angle
where they are tangent to each other. Angle History of geometry Non-Archimedean geometry Thomas Little Heath, T.L. (1908). The thirteen books of Euclid's
Horn_angle
Method of drawing geometric objects
constructed using compass alone, or by straightedge alone if given a single circle and its center. Ancient Greek mathematicians first conceived straightedge-and-compass
Straightedge and compass construction
Straightedge_and_compass_construction
Property of spirals
pitch angles that vary by distance from the center of the spiral. For an Archimedean spiral the angle decreases with the distance, while for a hyperbolic
Pitch_angle_of_a_spiral
Geometry where the axiom of Archimedes is negated
In mathematics, non-Archimedean geometry is any of a number of forms of geometry in which the axiom of Archimedes is negated. An example of such a geometry
Non-Archimedean_geometry
Construction of an angle equal to one third a given angle
and thus the correctness of the construction. Trisection using the Archimedean spiral Trisection using the Maclaurin trisectrix There are certain curves
Angle_trisection
Coordinates comprising a distance and an angle
known of these curves are the polar rose, Archimedean spiral, lemniscate, limaçon, and cardioid. For the circle, line, and polar rose below, it is understood
Polar_coordinate_system
Curve traced by a string as it is unwrapped from another curve
and a = 1 {\displaystyle a=1} (light blue). The involutes look like Archimedean spirals, but they are actually not. The arc length for a = 0 {\displaystyle
Involute
The area cut off by a secant of a smooth convex oval is not an algebraic function
If the oval is a circle centered at the origin, then the spiral constructed by Newton is an Archimedean spiral.
Newton's_theorem_about_ovals
Spiral that surrounds equal area per turn
double point free curve, in contrast with the Archimedean and hyperbolic spiral. Like a line or circle or parabola, it divides the plane into two connected
Fermat's_spiral
Number, approximately 3.14
mathematical constant, approximately equal to 3.14159, that is the ratio of a circle's circumference to its diameter. It appears in many formulae across mathematics
Pi
Group with translationally invariant total order
left-orderable. Otto Hölder showed that every Archimedean group (a bi-ordered group satisfying an Archimedean property) is isomorphic to a subgroup of the
Linearly_ordered_group
Relationship between two lines that meet at a right angle
circle is perpendicular to the tangent line to that circle at the point where the diameter intersects the circle. A line segment through a circle's center
Perpendicular
Regular tiling of the plane
1 and 3, while 111213 is reduced from 121314. There is one class of Archimedean colorings, 111112, (marked with a *) which is not 1-uniform, containing
Triangular_tiling
Number representing a continuous quantity
but it is the only uniformly complete Archimedean field, and indeed one often hears the phrase "complete Archimedean field" instead of "complete ordered
Real_number
Natural number
squares in the truncated square tiling. This tiling is one of eight Archimedean tilings that are semi-regular, or made of more than one type of regular
8
5th–6th century Greek mathematician
c. 520s) was a Greek mathematician who wrote commentaries on several Archimedean treatises and on the Apollonian Conics. Little is known about the life
Eutocius_of_Ascalon
If a smooth plane curve has monotonic curvature, then its osculating circles are nested
then the osculating circles of the curve are disjoint and nested within each other. The logarithmic spiral or the pictured Archimedean spiral provide examples
Tait–Kneser_theorem
Curve created by a geometric operation
Fermat's Last Theorem. As an example involving transcendental curves, the Archimedean spiral and hyperbolic spiral are inverse curves. Similarly, the Fermat
Inverse_curve
Sphere tangent to every face of a polyhedron
authorities agree that the Archimedean polyhedra (having regular faces and equivalent vertices) have no inspheres while the Archimedean dual or Catalan polyhedra
Inscribed_sphere
Part of a line that is bounded by two distinct end points; line with two endpoints
vertices, or a diagonal. When the end points both lie on a curve (such as a circle), a line segment is called a chord (of that curve). If V is a vector space
Line_segment
Semiregular tiling of the plane
The 2-uniform tilings are also called Archimedean colorings. There are infinite variations of these Archimedean colorings by arbitrary shifts in the square
Elongated_triangular_tiling
Problems which attempt to find the most efficient way to pack objects into containers
other shapes have received attention, including ellipsoids, Platonic and Archimedean solids including tetrahedra, tripods (unions of cubes along three positive
Packing_problems
Uniform tiling of the Euclidean plane
regular polygons List of uniform tilings Conway, 2008, Chapter 21, Naming Archimedean and Catalan polyhedra and tilings, p288 table Chavey, D. (1989). "Tilings
Truncated_trihexagonal_tiling
Reuleaux triangle Salinon Semicircle Stadium Tomahawk Trefoil Triquetra Archimedean spiral Astroid Cardioid Deltoid Ellipse Various lemniscates Nephroid
List of two-dimensional geometric shapes
List_of_two-dimensional_geometric_shapes
Field of mathematics which studies incidence structures
A similar bound for the number of incidences is conjectured for point-circle incidences, but only weaker upper bounds are known. Beck's theorem says
Incidence_geometry
Spiral asymptotic to a line
unlike the constant angles of logarithmic spirals or decreasing angles of Archimedean spirals. As this curve widens, it approaches an asymptotic line. It can
Hyperbolic_spiral
Branch of geometry that studies combinatorial properties and constructive methods
discrete sets of basic geometric objects, such as points, lines, planes, circles, spheres, polygons, and so forth. The subject focuses on the combinatorial
Discrete_geometry
Branch of mathematics
plane Branches Euclidean Non-Euclidean Elliptic Spherical Hyperbolic Non-Archimedean geometry Projective Affine Synthetic Analytic Algebraic Arithmetic Diophantine
Noncommutative_geometry
2019. Carter, Ithiel; Rodin, Burt (December 1992). "An Inverse Problem for Circle Packing and Conformal Mapping". Transactions of the American Mathematical
List_of_spirals
Semiregular tiling of the Euclidean plane
the original on 2010-09-19. Retrieved 2012-01-20. (Chapter 21, Naming Archimedean and Catalan polyhedra and tilings, p. 288, table) Five space-filling
Snub_trihexagonal_tiling
Type of non-Euclidean geometry
by selecting a small enough circle. If the Gaussian curvature of the plane is −1 then the geodesic curvature of a circle of radius r is: 1 tanh ( r
Hyperbolic_geometry
Mathematical treatise by Archimedes
{1}{3}},} which is an elementary result in integral calculus. Instead, the Archimedean method mechanically balances the parabola (the curved region being integrated
The Method of Mechanical Theorems
The_Method_of_Mechanical_Theorems
Shape with six sides
circumscribed circle) and tangential (has an inscribed circle). The common length of the sides equals the radius of the circumscribed circle or circumcircle
Hexagon
Method of describing higher-order polyhedra
operators. Conway's basic operations are sufficient to generate the Archimedean and Catalan solids from the Platonic solids. Some basic operations can
Conway_polyhedron_notation
Semiregular tiling of the Euclidean plane
Symmetries of Things 2008, ISBN 978-1-56881-220-5 [1] (Chapter 21, Naming Archimedean and Catalan polyhedra and tilings. Weisstein, Eric W. "Uniform tessellation"
Rhombitrihexagonal_tiling
Straight figure with zero width and depth
according to that relationship. For instance, with respect to a conic (a circle, ellipse, parabola, or hyperbola), lines can be: tangent lines, which touch
Line_(geometry)
Tiling of a plane by regular hexagons and equilateral triangles
; Burgiel, Heidi; Goodman-Strauss, Chaim (2008). "Chapter 21: Naming Archimedean and Catalan polyhedra and tilings; Euclidean plane tessellations". The
Trihexagonal_tiling
In mathematics, straight line touching a plane curve without crossing it
the curve. Archimedes (c. 287 – c. 212 BC) found the tangent to an Archimedean spiral by considering the path of a point moving along the curve. In
Tangent
Branch of mathematics
points, not all complex analytic varieties are manifolds. Over a non-archimedean field analytic geometry is studied via rigid analytic spaces. Modern
Algebraic_geometry
Plane spiral projected onto the surface of a cone
projection of the floor plan spiral onto the cone. 1) Starting with an archimedean spiral r ( φ ) = a φ {\displaystyle \;r(\varphi )=a\varphi \;} gives
Conical_spiral
Euclidean geometry without distance and angles
plane Branches Euclidean Non-Euclidean Elliptic Spherical Hyperbolic Non-Archimedean geometry Projective Affine Synthetic Analytic Algebraic Arithmetic Diophantine
Affine_geometry
Symbol with three-fold rotational symmetry
from a common center. The spiral design can be based on interlocking Archimedean spirals, or represent three bent human limbs. It occurs in artefacts
Triskelion
Catalan solid with 24 faces
kiscube) is a Catalan solid. Its dual is the truncated octahedron, an Archimedean solid. It can be called a disdyakis hexahedron or hexakis tetrahedron
Tetrakis_hexahedron
Branch of differential geometry and differential topology
plane Branches Euclidean Non-Euclidean Elliptic Spherical Hyperbolic Non-Archimedean geometry Projective Affine Synthetic Analytic Algebraic Arithmetic Diophantine
Symplectic_geometry
Non-Euclidean geometry
elliptic lines correspond to great circles reduced by the identification of antipodal points. As any two great circles intersect, there are no parallel
Elliptic_geometry
Distance along a curve
calculated from the original definitions by less than one part in 10,000. Archimedean spiral § Arc length Cycloid § Arc length Ellipse § Arc length Helix § Arc
Arc_length
Horopter Isochrone Pursuit curve Rhumb line Syntractrix Tractrix Trochoid Archimedean spiral Cornu spiral Fermat's spiral Hyperbolic spiral Lituus Logarithmic
Gallery_of_curves
3rd century calculation of π by Liu Hui
mathematics. It was based on calculation of N-gon area, in contrast to the Archimedean algorithm based on polygon circumference. With this method Zu Chongzhi
Liu_Hui's_π_algorithm
Semiregular tiling
the original on 2010-09-19. Retrieved 2012-01-20. (Chapter 21, Naming Archimedean and Catalan polyhedra and tilings, p288 table) Stephenson, John (1970)
Truncated_square_tiling
of Varignon[2] Lamé curve Pursuit curve Rhumb line Sinusoid Spirals Archimedean spiral Cornu spiral Cotes' spiral Fermat's spiral Galileo's spiral [3]
List_of_curves
Mathematical space with two coordinates
plane Branches Euclidean Non-Euclidean Elliptic Spherical Hyperbolic Non-Archimedean geometry Projective Affine Synthetic Analytic Algebraic Arithmetic Diophantine
Two-dimensional_space
Mathematical model of the physical space
areas of various figures in two and three dimensions, and enunciated the Archimedean property of finite numbers. Apollonius of Perga (c. 240 BCE – c. 190
Euclidean_geometry
Geometric space with four dimensions
further 58 convex uniform 4-polytopes, analogous to the 13 semi-regular Archimedean solids in three dimensions. Relaxing the conditions for convexity generates
Four-dimensional_space
Geometric figure which has infinite surface area but finite volume
following year included that paper and a second more orthodox (for the time) Archimedean proof of its theorem about the volume of a truncated acute hyperbolic
Gabriel's_horn
Function in algebra
minimum convention. Every Archimedean group is isomorphic to a subgroup of the real numbers under addition, but non-Archimedean ordered groups exist, such
Valuation_(algebra)
Geometry of the surface of a sphere
picture, a great circle is the intersection of the sphere with any plane through the center. In the intrinsic approach, a great circle is a geodesic; a
Spherical_geometry
Geometric model of the planar projection of the physical universe
also metrical properties induced by a distance, which allows to define circles, and angle measurement. A Euclidean plane with a chosen Cartesian coordinate
Euclidean_plane
Geometry without using coordinates
plane Branches Euclidean Non-Euclidean Elliptic Spherical Hyperbolic Non-Archimedean geometry Projective Affine Synthetic Analytic Algebraic Arithmetic Diophantine
Synthetic_geometry
Uniform tiling of the hyperbolic plane
Symmetries of Things 2008, ISBN 978-1-56881-220-5 (Chapter 19, The Hyperbolic Archimedean Tessellations) "Chapter 10: Regular honeycombs in hyperbolic space".
Alternated_octagonal_tiling
Space with one dimension
ambient space in which the line or curve is embedded. Examples include the circle on a plane, or a parametric space curve. In physical space, a 1D subspace
One-dimensional_space
Sphere tangent to every edge of a polyhedron
Coxeter (1973) states this for regular polyhedra; Cundy & Rollett 1961 for Archimedean polyhedra. Pugh (1976). László (2017). The irregular tetrahedra with
Midsphere
Isogonal polyhedron with regular faces
and antiprisms, the convex polyhedrons as in 5 Platonic solids and 13 Archimedean solids—2 quasiregular and 11 semiregular— the non-convex star polyhedra
Uniform_polyhedron
Notation for a polyhedron's vertex figure
It is also called a Cundy and Rollett symbol for its usage for the Archimedean solids in their 1952 book Mathematical Models. For uniform polyhedra
Vertex_configuration
Leibniz Isochrone of Varignon Lamé curve Pursuit curve Rhumb line Spirals Archimedean spiral Cornu spiral Cotes' spiral Fermat's spiral Galileo's spiral Hyperbolic
List_of_mathematical_shapes
Topological space of dimension zero
plane Branches Euclidean Non-Euclidean Elliptic Spherical Hyperbolic Non-Archimedean geometry Projective Affine Synthetic Analytic Algebraic Arithmetic Diophantine
Zero-dimensional_space
Periodic tiling of the hyperbolic disk
Symmetries of Things 2008, ISBN 978-1-56881-220-5 (Chapter 19, The Hyperbolic Archimedean Tessellations) "Chapter 10: Regular honeycombs in hyperbolic space".
Order-3_apeirogonal_tiling
Relation between sides of a right triangle
related as follows: the sum of the areas of the circles with diameters a and b equals the area of the circle with diameter c. For any right triangle on a
Pythagorean_theorem
Ranges of numbers contained in each other
+} and ⋅ {\displaystyle \cdot } is an Archimedean ordered field, meaning the axioms of order and the Archimedean property hold. Source: Let ( I n ) n ∈
Nested_intervals
Self-similar curve related to golden ratio
Although spiral galaxies have often been modeled as logarithmic spirals, Archimedean spirals, or hyperbolic spirals, their pitch angles vary with distance
Golden_spiral
ARCHIMEDEAN CIRCLE
ARCHIMEDEAN CIRCLE
Surname or Lastname
English (Essex, Cambridgeshire)
English (Essex, Cambridgeshire) : possibly a variant of Trendall, a topographic name for someone who lived by a well, earhwork, stone circle, or other circular feature, from Middle English trendel, trandle ‘circle’ (Old English trendel).Possibly an altered spelling of South German Tröndle, a variant of Trendle, a nickname for a tearful person, from Träne ‘tear’ + the diminutive suffix -l.
Boy/Male
French Israeli
The circle.
Girl/Female
Latin
Circle of light.
Girl/Female
Welsh Arthurian Legend Celtic
Fair. Blessed. White browed. White circle.
Girl/Female
Japanese
Ball; circle.
Girl/Female
Welsh
Fair. Blessed. White browed. White circle.
Girl/Female
Latin
Circle of light.
Girl/Female
Hindu
Lord Buddha, Energy circle or a form of chakra
Girl/Female
Welsh American
Fair. Blessed. White browed. White circle.
Girl/Female
Welsh
Fair. Blessed. White browed. White circle.
Surname or Lastname
English
English : habitational name from a place in Norfolk, recorded in Domesday Book as Huerueles, named in Old English as hwerflas ‘circles’.
Boy/Male
Greek Latin
To think about first.
Girl/Female
Welsh American
Fair. Blessed. White browed. White circle.
Girl/Female
Tamil
Lord Buddha, Energy circle or a form of chakra
Girl/Female
Welsh
Fair. Blessed. White browed. White circle.
Girl/Female
Tamil
Shaakya | ஷாகà¯à®¯à®¾à®‚
Lord Buddha, Energy circle or a form of chakra
Shaakya | ஷாகà¯à®¯à®¾à®‚
Surname or Lastname
English, German, and Dutch
English, German, and Dutch : metonymic occupational name for a maker of rings (from Middle English ring, Middle High German rinc, Middle Dutch ring), either to be worn as jewelry or as component parts of chain-mail, harnesses, and other objects. In part it may also have arisen as a nickname for a wearer of a ring.Scandinavian : from ring ‘ring’, probably an ornamental name but possibly applied in the same sense as 3 or 1.German : topographic name from Middle High German, Middle Low German rink, rinc ‘circle’.Irish (eastern County Cork) : reduced Anglicized form of Gaelic Ó Rinn (see Reen).
Girl/Female
Hindu
Lord Buddha, Energy circle or a form of chakra
Girl/Female
Latin
Circle of light.
Surname or Lastname
English
English : habitational name from any of the places called Wilby, in Suffolk, Norfolk, and Northamptonshire. The first is probably named from an Old English wilig ‘willow’ + Old English bēag ‘circle’; the second has the same first element + Old Norse býr ‘farmstead’ or Old English bēag, and the last is named with the Old English or Old Scandinavian personal name Villi + býr.
ARCHIMEDEAN CIRCLE
ARCHIMEDEAN CIRCLE
ARCHIMEDEAN CIRCLE
ARCHIMEDEAN CIRCLE
ARCHIMEDEAN CIRCLE
ARCHIMEDEAN CIRCLE
ARCHIMEDEAN CIRCLE
n.
One of the two small circles of the celestial sphere, situated on each side of the equator, at a distance of 23¡ 28/, and parallel to it, which the sun just reaches at its greatest declination north or south, and from which it turns again toward the equator, the northern circle being called the Tropic of Cancer, and the southern the Tropic of Capricorn, from the names of the two signs at which they touch the ecliptic.
n.
Any definite quantity, or aggregate of quantities or magnitudes taken as one, or for which 1 is made to stand in calculation; thus, in a table of natural sines, the radius of the circle is regarded as unity.
v. i.
To move circularly; to form a circle; to circulate.
n.
A mass of fluid, especially of a liquid, having a whirling or circular motion tending to form a cavity or vacuum in the center of the circle, and to draw in towards the center bodies subject to its action; the form assumed by a fluid in such motion; a whirlpool; an eddy.
a.
Of or pertaining to Archimedes, a celebrated Greek philosopher; constructed on the principle of Archimedes' screw; as, Archimedean drill, propeller, etc.
a.
Having the form of a circle; round.
n.
An instrument of observation, the graduated limb of which consists of an entire circle.
n.
An extinct genus of Bryzoa characteristic of the subcarboniferous rocks. Its form is that of a screw.
imp. & p. p.
of Circle
a.
Not symmetrical; being without symmetry, as the parts of a flower when similar parts are of different size and shape, or when the parts of successive circles differ in number. See Symmetry.
n.
A vertical line, plane, or circle.
n.
A little circle; esp., an ornament for the person, having the form of a circle; that which encircles, as a ring, a bracelet, or a headband.
n.
Any one of several species of actinians belonging to the genus Cerianthus. These animals have a long, smooth body tapering to the base, and two separate circles of tentacles around the mouth. They form a tough, flexible, feltlike tube with a smooth internal lining, in which they dwell, whence the name.
n.
A circumference; a circle; a ring.
n.
A circle either of leaves or flowers about a stem at the same node; a whorl.
n.
To encompass, as by a circle; to surround; to inclose; to encircle.
n.
Any one of numerous species of ciliated Infusoria belonging to Vorticella and many other genera of the family Vorticellidae. They have a more or less bell-shaped body with a circle of vibrating cilia around the oral disk. Most of the species have slender, contractile stems, either simple or branched.
n.
A young larval form of many annelids, mollusks, and bryozoans, in which a circle of cilia is developed around the anterior end.