a completely round, plain shape

(geometry) a flat shape consisting of three straight sides and three angles

(geometry) a flat shape with four right angles, especially one with opposing sides that are equal and parallel to each other

a quadrilateral shape with two pairs of congruent sides that are connected at a right angle, with one pair longer than the other

a shape with four equal straight sides and four right angles (90°)

(geometry) a flat shape with four flat sides, two of which are parallel

(geometry) any flat shape with four straight sides, the opposite sides of which are equal and parallel to each other

(geometry) a flat shape with four equal sides in which opposite angles are equal

(geometry) a flat shape consisting of three or more straight sides

(geometry) a flat shape consisting of three straight sides and one right angle

a triangle that contains no right angle

a triangle with no two sides of equal length

a type of triangle that has two sides of equal length and two angles of equal measure

a three-sided regular polygon

a triangle that contains an obtuse interior angle

(geometry) a parallelogram with four straight sides and no right angles

any half of a circle

a three-dimensional geometric shape resembling a donut or a ring, formed by rotating a circle around an axis that doesn't intersect the circle's plane

(geometry) a figure with four sides and two opposite angles more than 90° and two of less than 90°

a rectangular figure that has unequal adjacent sides with arched angles

a shape that is wide in the middle and narrow at both ends