alternate angles

American  

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.

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alternate angles British  

plural noun

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

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alternate angles Scientific  

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.

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Etymology

Origin of alternate angles

First recorded in 1650–60