plane figure

/pleɪn ˌfɪgjər/

Other forms: plane figures

Definitions of plane figure

1. noun

   a two-dimensional shape
   synonyms: two-dimensional figure

   types:

   heart

   a plane figure with rounded sides curving inward at the top and intersecting at the bottom; conventionally used on playing cards and valentines

   polygon, polygonal shape

   a closed plane figure bounded by straight sides

   conic, conic section

   (geometry) a curve generated by the intersection of a plane and a circular cone

   oblong

   a plane figure that deviates from a square or circle due to elongation

   hemicycle, semicircle

   a shape with one straight side and one round side

   sector

   a plane figure bounded by two radii and the included arc of a circle

   star

   a plane figure with 5 or more points; often used as an emblem

   paraboloid

   a surface having parabolic sections parallel to a single coordinate axis and elliptic sections perpendicular to that axis

   ellipsoid

   a surface whose plane sections are all ellipses or circles

   tree, tree diagram

   a figure that branches from a single root

   isogon

   an equiangular polygon

   convex polygon

   a polygon such that no side extended cuts any other side or vertex; it can be cut by a straight line in at most two points

   concave polygon

   a polygon such that there is a straight line that cuts it in four or more points

   ellipse, oval

   a closed plane curve resulting from the intersection of a circular cone and a plane cutting completely through it

   quadrangle, quadrilateral, tetragon

   a four-sided polygon

   triangle, trigon, trilateral

   a three-sided polygon

   hexagram

   a regular polygon formed by extending each of the sides of a regular hexagon to form two equilateral triangles

   asterism

   (mineralogy) a star-shaped figure with six rays that is seen in some crystal structures under reflected or transmitted light

   pentacle, pentagram, pentangle

   a star with 5 points; formed by 5 straight lines between the vertices of a pentagon and enclosing another pentagon

   pentagon

   a five-sided polygon

   hexagon

   a six-sided polygon

   heptagon

   a seven-sided polygon

   octagon

   an eight-sided polygon

   nonagon

   a nine-sided polygon

   decagon

   a polygon with 10 sides and 10 angles

   undecagon

   an eleven-sided polygon

   dodecagon

   a twelve-sided polygon

   spherical polygon

   a figure on the surface of a sphere bounded by arcs of 3 or more great circles

   parabola

   (mathematics) the graph of a quadratic function: a symmetrical, approximately U-shaped curve, such as the path of an object that is thrown into the air and falls some distance away

   hyperbola

   an open curve formed by a plane that cuts the base of a right circular cone

   cladogram

   a tree diagram used to illustrate phylogenetic relationships

   stemma

   a tree diagram showing a reconstruction of the transmission of manuscripts of a literary work

   type of:

   figure

   a combination of points and lines and planes that form a visible palpable shape