Two numbers that are located the same distance from 0 on the number line but in opposite directions. The sum of opposite numbers is 0.

Two numbers whose sum is 0.

two quantities whose sum is 0 (also called additive inverses). Perfect Square Trinomial-a polynomial of three terms that factors into the same two binomials.

The differentiation of ego-consciousness from unconscious contents.

Opposites are things that are very, very different from each other. Some examples of opposites are: positive and negative, add and subtract, left and right, big and small, up and down.

See Opposites principle