Geometry Terms

Parallel

• Lines that are always the same distance apart and will never intersect (cross).

• Lines that meet at a right angle.

• Lines that converge at a point.

• Lines that are always different distances apart.

Parallelograms

• A three-dimensional shape with 6 faces.

• A two-dimensional flat shape with 4 sides with both pairs of opposite sides parallel.

• A shape with only one pair of parallel sides.

• A polygon with more than four sides.

Line of Symmetry

• A line that divides a shape into two equal parts.

• A real or imaginary line that divides a shape into two mirror images.

• A line that represents the boundary of a shape.

• A line that connects two opposite points of a shape.

Quadrilaterals

• A three-dimensional shape with 4 sides.

• A two-dimensional shape with 4 sides.

• A two-dimensional shape with 3 sides.

• A shape with 4 angles and no sides.

Right Angles

• An angle with a measure that is exactly 90 degrees.

• An angle that measures 45 degrees.

• An angle that measures 180 degrees.

• An angle that measures 360 degrees.

Rhombus

• A two-dimensional shape with 4 congruent sides.

• A three-dimensional shape with 6 faces.

• A two-dimensional shape with 4 right angles.

• A polygon with 5 sides.

Vertex/Corner

• The point at which the sides of a two-dimensional shape or edges of a three-dimensional shape intersect.

• A line segment that connects two points on a shape.

• The area enclosed by the sides of a shape.

• The distance around a shape.

Square

• A two-dimensional shape with 4 congruent sides and 4 right angles.

• A three-dimensional shape with 6 faces, all of which are rectangles.

• A two-dimensional shape with 3 sides and 3 angles.

• A two-dimensional shape with 4 sides of different lengths.

Perpendicular

• Intersection at right angles.

• Lines that never meet.

• Angles that are less than 90 degrees.

• A type of parallel line.

Trapezoid

• A two-dimensional shape with four sides and exactly one pair of parallel sides.

• A three-dimensional shape with four triangular faces.

• A two-dimensional shape with four sides and no parallel sides.

• A two-dimensional shape with three sides and one right angle.