We found 26 dictionaries that define the word nonagon:

General (20 matching dictionaries)

1. nonagon: Merriam-Webster
2. nonagon: Oxford Learner's Dictionaries
3. nonagon: American Heritage Dictionary of the English Language
4. nonagon: Collins English Dictionary
5. nonagon: Vocabulary.com
6. nonagon: Wordnik
7. nonagon: Wiktionary
8. nonagon: Webster's New World College Dictionary, 4th Ed.
9. nonagon: The Wordsmyth English Dictionary-Thesaurus
10. nonagon: Infoplease Dictionary
11. Nonagon, nonagon: Dictionary.com
12. Nonagon: Wikipedia, the Free Encyclopedia
13. Nonagon: Online Plain Text English Dictionary
14. nonagon: Webster's Revised Unabridged, 1913 Edition
15. nonagon: Rhymezone
16. Nonagon: AllWords.com Multi-Lingual Dictionary
17. nonagon: Webster's 1828 Dictionary
18. nonagon: FreeDictionary.org
19. nonagon: Mnemonic Dictionary
20. nonagon: TheFreeDictionary.com

Art (1 matching dictionary)

21. nonagon: ArtLex Lexicon of Visual Art Terminology

Computing (1 matching dictionary)

22. nonagon: Encyclopedia

Medicine (1 matching dictionary)

23. online medical dictionary (No longer online)

Science (2 matching dictionaries)

24. nonagon: LITTLE EXPLORERS(TM) Picture Dictionary
25. Nonagon: Eric Weisstein's World of Mathematics

Slang (1 matching dictionary)

26. nonagon: Urban Dictionary

(Note: See nonagons as well.)

Definitions from Wiktionary (nonagon) ▸ noun:  (geometry) A polygon with nine sides and nine angles; an enneagon. Similar: enneagon, enneadecagon, enneacontahexagon, undecagon, decagon, icosagon, exagon, septagon, hendecagon, hexadecagon, more... Types: heptadecagon, octadecagon, enneadecagon, decagon, hendecagon, dodecagon, more... Phrases: Nonagon Infinity, more... ▸ Words similar to nonagon ▸ Usage examples for nonagon ▸ Idioms related to nonagon ▸ Wikipedia articles (New!) ▸ Popular adjectives describing nonagon ▸ Words that often appear near nonagon ▸ Rhymes of nonagon ▸ Invented words related to nonagon