Definition

Noun: A nonagon is a two-dimensional geometric shape, specifically a polygon, that has exactly nine straight sides and nine angles.

Usage

The word nonagon is used in mathematical and geometric contexts to describe a specific type of polygon. It is a precise term. * A stop sign is an octagon, but a regular nonagon has one more side. * The architect incorporated a nonagon into the design of the courtyard.

Advanced Usage

• Regular Nonagon: A nonagon where all nine sides are of equal length and all nine interior angles are equal (each measuring 140 degrees).
  • Calculating the area of a regular nonagon requires a specific formula.
• Irregular Nonagon: A nonagon where the sides and angles are not all equal.
  • The irregular nonagon she drew had sides of varying lengths.

Variants and Related Words

• Enneagon: A less common synonym for nonagon, also meaning a nine-sided polygon. (Derived from Greek , meaning 'nine').
• Polygon: The general category of shapes to which a nonagon belongs.
• Nonagonal (adjective): Relating to or shaped like a nonagon.
  • The nonagonal pattern was visually striking.

Synonyms

• Enneagon (noun): A nine-sided polygon. (Note: This is a direct synonym, though 'nonagon' is more commonly used in general English).

Different Meanings

The word nonagon has only one primary meaning in English: a nine-sided polygon. It does not have other common definitions or idiomatic uses.

Noun

1. a nine-sided polygon