Definition

1. Noun:
   • The angle inside two adjacent sides of a polygon: An interior angle is the angle formed on the inside of a polygon where two sides meet at a vertex.

Usage

• The term "interior angle" is used in geometry to describe and calculate the internal angles of polygons.
• It is typically measured in degrees.
• The sum of all interior angles in a polygon is determined by the formula (n-2) × 180°, where 'n' is the number of sides.

Examples

• Noun:
  • In a square, each interior angle measures 90 degrees.
  • To find the sum of the interior angles of a hexagon, use the formula (6-2) × 180°.
  • The interior angle at the vertex of the triangle was acute.

Advanced Usage

• "Remote interior angles": In a triangle, the two interior angles that are not adjacent to a given exterior angle.
  • An exterior angle of a triangle is equal to the sum of its two remote interior angles.

Variants and Related Words

• Internal angle: A synonym for interior angle.
• Exterior angle (n): The angle formed outside a polygon when one side is extended. It is supplementary to the adjacent interior angle.
  • The exterior angle and its adjacent interior angle always add up to 180°.

Synonyms

• Internal angle

Antonyms

• Exterior angle: The angle formed outside the polygon.

Noun

1. the angle inside two adjacent sides of a polygon