alternate angles

plural noun

Geometry.

1. two nonadjacent angles made by the crossing of two lines by a third line, both angles being either interior or exterior, and being on opposite sides of the third line.

alternate angles

plural noun

1. two angles at opposite ends and on opposite sides of a transversal cutting two lines

alternate angles

1. Two angles formed on opposite sides of a line that crosses two other lines. The angles are both exterior or both interior, but not adjacent.

Word History and Origins

Origin of alternate angles¹

First recorded in 1650–60