- an angle formed between parallel lines by a third line that intersects them.
- an angle formed within a polygon by two adjacent sides.
Origin of interior angle
First recorded in 1750–60
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- an angle of a polygon contained between two adjacent sides
- any of the four angles made by a transversal that lie inside the region between the two intersected lines
- Any of the four angles formed inside two straight lines when these lines are intersected by a third straight line.
- An angle formed by two adjacent sides of a polygon and included within the polygon. Compare exterior angle.
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