Definition

1. Noun:
   • The angle inside two adjacent sides of a polygon: An "internal angle" (also called an interior angle) is the angle formed on the inside of a polygon where two sides meet at a vertex.

Usage

• The term "internal angle" is used in geometry to describe a fundamental property of polygons.
• It is typically measured in degrees or radians.
• The sum of all internal angles in a polygon depends on the number of sides.

Examples

• Noun:
  • In a square, each internal angle measures 90 degrees.
  • To find the sum of the internal angles of a hexagon, you can use the formula (n-2) × 180°, where n is the number of sides.
  • The internal angle at the vertex of the triangle was acute.

Advanced Usage

• "Internal angle sum": Refers to the total of all interior angles in a polygon.
  • The internal angle sum of a pentagon is 540 degrees.
• "Measure of an internal angle": Specifies the size of a particular interior angle.
  • The problem asks for the measure of one internal angle in a regular octagon.

Variants and Related Words

• Interior angle (n): A complete synonym for "internal angle."
  • The interior angles of a triangle always add up to 180°.
• External angle (n): The angle formed outside a polygon between one side and the extension of an adjacent side.
  • An external angle and its corresponding internal angle are supplementary.

Synonyms

• Interior angle: The angle on the inside of a polygon.

Antonyms

• External angle: The angle on the outside of a polygon, formed by extending one of its sides.

Noun

1. the angle inside two adjacent sides of a polygon