Geometry Basic Vocabulary

Front

What is a quadrilateral?

Back

A polygon with four sides, four angles, and four vertices.

Front

polygon

Back

a 2-d closed shape with 3 or more sides

Front

parallel lines

Back

lines that are the same distance apart and never cross

Front

Back

parallel lines

Front

trapezoid

Back

a quadilateral with exactly one pair of parallel lines

Front

rhombus

Back

a quadrilateral with 4 congruent (equal sides)

Front

parallelogram

Back

a quadrilateral with two pairs of parallel lines

Front

rectangle

Back

a quadrilateral with four right angles; opposite sides are parallel and congruent

Front

square

Back

a quadrilateral with four right angles; opposite sides are parallel; all four sides are congruent (equal in length)

Front

acute angle

Back

An angle that is LESS than a right angle (90 degrees)