Geometry Vocabulary

Triangle with one angle of 90 degrees

• right

• acute

• equilateral

• obtuse

Any quadrilateral with four sides sides with same length

• polygon

• quadriateral

• square

• rhombus

Any closed two-dimensional figure with at least three straight sides

• polygon

• circle

• square

• parallelogram

Two-dimensional shape that is NOT classified as a polygon

• circle

• square

• trapezoid

• rhombus

Quadrilateral with one pair of parallel sides

• parallelogram

• trapezoid

• rectangle

• square

Triangle with all angles same length and all angles same size

• isosceles

• equilateral

• scalene

• acute

Quadrilateral with four sides same length and four right angles

• polygon

• parallelogram

• square

• rectangle

Triangle with at least two sides same length

• isosceles

• equilateral

• scalene

• acute

Any polygon with four sides, angles, vertices

• quadrilateral

• square

• rectangle

• parallelogram

Lines that intersect and form a right angle

• perpendicular

• parallel

• congruent

• right