List of circle topics
This list of circle topics includes things related to the geometric shape, either abstractly, as in idealizations studied by geometers, or concretely in physical space. It does not include metaphors like "inner circle" or "circular reasoning" in which the word does not refer literally to the geometric shape.
Geometry and other areas of mathematics
- Circle anatomy
- Annulus (mathematics)
- Area of a disk
- Bipolar coordinates
- Central angle
- Circular sector
- Circular segment
- Circumference
- Concentric
- Concyclic
- Degree (angle)
- Diameter
- Disk (mathematics)
- Horn angle
- Measurement of a Circle
- π
- Pole and polar
- Power of a point
- Radical axis
- Radius
- Sphere
- Tangent lines to circles
- Versor
- Specific circles
- Apollonian circles
- Circles of Apollonius
- Archimedean circle
- Archimedes' circles – the twin circles doubtfully attributed to Archimedes
- Archimedes' quadruplets
- Circle of antisimilitude
- Bankoff circle
- Brocard circle
- Carlyle circle
- Circumscribed circle (circumcircle)
- Coaxal circles
- Director circle
- Fermat–Apollonius circle
- Ford circle
- Fuhrmann circle
- Generalised circle
- GEOS circle
- Great circle
- Horocycle
- Incircle and excircles of a triangle
- Inscribed circle
- Johnson circles
- Magic circle (mathematics)
- Malfatti circles
- Nine-point circle
- Orthocentroidal circle
- Osculating circle
- Riemannian circle
- Schinzel circle
- Schoch circles
- Spieker circle
- Tangent circles
- Twin circles
- Unit circle
- Van Lamoen circle
- Villarceau circles
- Woo circles
- Circle-derived entities
- Apollonian gasket
- Arbelos
- Bicentric polygon
- Bicentric quadrilateral
- Coxeter's loxodromic sequence of tangent circles
- Cyclic quadrilateral
- Cycloid
- Ex-tangential quadrilateral
- Hawaiian earring
- Inscribed angle
- Inscribed angle theorem
- Inversive distance
- Inversive geometry
- Irrational rotation
- Lens (geometry)
- Lune
- Lazy caterer's sequence
- Overlapping circles grid
- Pappus chain
- Polar circle (geometry)
- Power center (geometry)
- Salinon
- Semicircle
- Squircle
- Steiner chain
- Tangential polygon
- Tangential quadrilateral
- Roulettes
- Topology
- Circle-related theory
- Apollonius' problem
- Belt problem
- Benz plane
- Bertrand's paradox (probability)
- Bonnesen's inequality
- Brahmagupta's formula
- Buffon's needle problem
- Bundle theorem
- Butterfly theorem
- Carnot's theorem
- Casey's theorem
- Circle graph
- Circle map
- Circle packing
- Circular surface
- Clifford's circle theorems
- Compass and straightedge
- Descartes' theorem
- Dinostratus' theorem
- Dividing a circle into areas
- Equal incircles theorem
- Five circles theorem
- Gauss circle problem
- Gershgorin circle theorem
- Geometrography
- Hadamard three-circle theorem
- Hardy–Littlewood circle method
- Isoperimetric problem
- Japanese theorem for cyclic polygons
- Japanese theorem for cyclic quadrilaterals
- Kosnita's theorem
- Lester's theorem
- Milne-Thomson circle theorem
- Miquel's theorem
- Monge's theorem
- Mrs. Miniver's problem
- Pivot theorem
- Pizza theorem
- Squaring the circle
- Poncelet's porism
- Ptolemy's theorem
- Ptolemy's table of chords
- Regiomontanus' angle maximization problem
- Ring lemma
- Seven circles theorem
- Six circles theorem
- Smallest circle problem
- Tammes problem
- Tarski's circle-squaring problem
- Thales' theorem
- Circle tangents in non-geometric theory
- Circle criterion
- Circle group
- Circular algebraic curve
- Circular distribution
- Circular statistics
- Mean of circular quantities
- Polygon-circle graph
- Splitting circle method
- von Mises distribution
- Wigner semicircle distribution
- Wrapped distribution
- Other topics
Physical sciences and engineering
- Centrifugal force
- Centripetal force
- Circle of confusion
- Circle of forces
- Circular dichroism
- Circular orbit
- Mohr's circle
- Non-uniform circular motion
- Thomson problem
- Uniform circular motion
Geography
- Arctic Circle
- Antarctic Circle
- Circle of latitude
- Equator
- Great-circle distance
- Polar circle
- Position circle
- Tropic of Cancer
- Tropic of Capricorn
Artifacts
- Addendum circle
- Belt problem
- Center pivot irrigation
- Circular ditches
- Circular slide rule
- Compass (drafting)
- Crop circle
- Dip circle
- List of gear nomenclature
- Peaucellier–Lipkin linkage
- Pitch circle
- Repeating circle
- Timber circle
- Traffic circle
- Setting circles
- Stone circle
- Wheel
Glyphs and symbols
- Borromean rings
- Circled dot (disambiguation)
- Circles in Polish mythology
- Crescent
- Dotted circle
- Enso
- Magic circle
- Olympic emblem
- Ouroboros
- Petosiris to Nechepso
- Quatrefoil
- Ring (diacritic)
- Roundel
- Sacred Chao
- Shield of the Trinity
- Solar symbols
- Squared-circle postmark
- Sun cross
- Symbol of Tanit
- Trefoil
- Triquetra
- Vesica piscis
- Triple Goddess symbol
- Yin and yang