9 terms

diagonal

in a polygon, a segment that connects nonconsecutive vertices of the polygon

isosceles trapezoid

a trapezoid in which the legs are congruent, both pairs of base angles are congruent, and the diagonals are congruent

kite

a quadrilateral with exactly two distinct pairs of adjacent congruent sides

median

in a trapezoid, the segment that joins the midpoints of the legs

parallelogram

a quadrilateral with parallel opposite sides. Any side of a parallelogram may be called a base

rectangle

a quadrilateral with four right angles

rhombus

a quadrilateral with all four sides congruent

square

a quadrilateral with four right angles and four congruent sides

trapezoid

a quadrilateral with exactly one pair of parallel sides. The parallel sides of a trapezoid are called bases. The nonparallel sides are called legs. The pairs of angles with their vertices at the end points of the same base are called base angles.