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nonagon

nonagon

7.6
A flat shape with nine straight sides and nine angles
  • noun
  • /ˈnɒnəˌɡɒn/
  • Specialized
translation icon : nonágono
  • A nonagon has nine sides.

Examples

  • The student drew a perfect nonagon for her geometry assignment.

  • The design on the floor was based on the shape of a nonagon.

  • A regular nonagon has equal sides and angles.

  • The nonagon is a fascinating shape in geometry.

  • A regular nonagon has equal sides and angles.

  • The design on the floor was based on the shape of a nonagon.

  • The student drew a perfect nonagon for her geometry assignment.

Synonyms

enneagon
vsnonagon
  • Specialized
9.9

A flat shape with nine straight sides and nine corners

is the identical concept but uses an alternate naming form

How Many Sides

dodecagon
  • Specialized
1 8.2
decagon
  • Specialized
6.7
nonagon
  • Specialized
7.6
octagon
7 3.3
hexagon
5 2.8
pentagon
1 3.0
triangle
58 1.0

Surface Forms

nonagon singular
nonagons plural

Morphology

nonagon = nona + gon

The word follows the regular polygon‑naming pattern (nona- 'nine' + -gon 'angle/side'), so the relationship is systematic, but the combining forms are not standalone English words and 'non-' could be misread as the negative prefix, making the formation only partially obvious to learners.

Etymology

Nonagon comes from two parts that mean 'nine' and 'angle'. The non- part is from an old word for 'nine' and the -gon part is the same as in hexagon and octagon, so a nonagon is a nine-sided, nine-angled shape.