What does "congruent" mean in geometry?

In geometry, the term congruent refers to two items being the same size and shape. Congruent can be used to describe shapes, sides, segments and/or angles.

Congruent shapes can undergo transformations and still have the same size, angles and line lengths. Transformations include rotation, reflection or translation. Rotation involves turning a shape, reflection is flipping the shape and translation occurs when the shape slides across a plane.

Congruent angles occur when multiple angles contain the same measure. On congruent shapes, the angles and sides can be marked with dashes and half circles.

The word "congruent" originates from the Latin term "congruere," which means "to agree."