List of two-dimensional geometric shapes

Template:Short description This is a list of two-dimensional geometric shapes in Euclidean and other geometries. For mathematical objects in more dimensions, see list of mathematical shapes. For a broader scope, see list of shapes.

Generally composed of straight line segments

• Angle
• Balbis
• Concave polygon
• Constructible polygon
• Convex polygon
• Cyclic polygon
• Equiangular polygon
• Equilateral polygon
• Penrose tile
• Polyform
• Regular polygon
• Simple polygon
• Tangential polygon

Polygons with specific numbers of sides

• Triangle – 3 sides
  • Acute triangle
  • Equilateral triangle
  • Heptagonal triangle
  • Isosceles triangle
    • Golden Triangle
  • Obtuse triangle
  • Rational triangle
  • Heronian triangle
    • Pythagorean triangle
    • Isosceles heronian triangle
    • Primitive Heronian triangle
  • Right triangle
    • 30-60-90 triangle
    • Isosceles right triangle
    • Kepler triangle
  • Scalene triangle
• Quadrilateral – 4 sides
  • Cyclic quadrilateral
  • Kite
    • Rectangle
    • Rhomboid
    • Rhombus
    • Square (regular quadrilateral)
  • Tangential quadrilateral
  • Trapezoid
    • Isosceles trapezoid
  • Trapezus
• Pentagon – 5 sides
• Hexagon – 6 sides
  • Lemoine hexagon
• Heptagon – 7 sides
• Octagon – 8 sides
• Nonagon – 9 sides
• Decagon – 10 sides
• Hendecagon – 11 sides
• Dodecagon – 12 sides
• Tridecagon – 13 sides
• Tetradecagon – 14 sides
• Pentadecagon – 15 sides
• Hexadecagon – 16 sides
• Heptadecagon – 17 sides
• Octadecagon – 18 sides
• Enneadecagon – 19 sides
• Icosagon – 20 sides
• Icosikaihenagon - 21 sides
• Icosikaidigon - 22 sides
• Icositrigon - 23 sides
• Icositetragon - 24 sides
• Icosikaipentagon - 25 sides
• Icosikaihexagon - 26 sides
• Icosikaiheptagon - 27 sides
• Icosikaioctagon - 28 sides
• Icosikaienneagon - 29 sides
• Triacontagon - 30 sides
• Tetracontagon - 40 sides
• Pentacontagon - 50 sides
• Hexacontagon - 60 sides
• Heptacontagon - 70 sides
• Octacontagon - 80 sides
• Enneacontagon - 90 sides
• Hectogon - 100 sides
• Dihectogon - 200 sides
• Trihectogon - 300 sides
• Tetrahectogon - 400 sides
• Pentahectogon - 500 sides
• Hexahectogon - 600 sides
• Heptahectogon - 700 sides
• Octahectogon - 800 sides
• Enneahectogon - 900 sides
• Chiliagon - 1,000 sides
• Myriagon - 10,000 sides
• Megagon - 1,000,000 sides
• Jangon - 1,000,000,000 sides
• Star polygon – there are multiple types of stars
  • Pentagram - star polygon with 5 sides
  • Hexagram – star polygon with 6 sides
    • Star of David (example)
  • Heptagram – star polygon with 7 sides
  • Octagram – star polygon with 8 sides
    • Star of Lakshmi (example)
  • Enneagram - star polygon with 9 sides
  • Decagram - star polygon with 10 sides
  • Hendecagram - star polygon with 11 sides
  • Dodecagram - star polygon with 12 sides
• Apeirogon - generalized polygon with countably infinite set of sides

Curved

Composed of circular arcs

• Annulus
• Arbelos
• Circle
  • Archimedes' twin circles
  • Bankoff circle
  • Circular triangle
    • Reuleaux triangle
  • Circumcircle
  • Disc
  • Incircle and excircles of a triangle
  • Nine-point circle
• Circular sector
• Circular segment
• Crescent
• Lens, vesica piscis (fish bladder)
• Lune
• Quatrefoil
• Reuleaux polygon
  • Reuleaux triangle
• Salinon
• Semicircle
• Tomahawk
• Trefoil
• Triquetra

Not composed of circular arcs

• Archimedean spiral
• Astroid
• Cardioid
• Deltoid
• Ellipse
• Various lemniscates
• Oval
  • Cartesian oval
  • Cassini oval
  • Oval of Booth
• Superellipse
• Taijitu
• Tomoe
• Magatama

See also

• List of triangle topics
• List of circle topics
• Glossary of shapes with metaphorical names