We found 24 dictionaries that define the word umpteen:

General (20 matching dictionaries)

1. umpteen: Longman Dictionary of Contemporary English
2. umpteen: Merriam-Webster
3. umpteen: Oxford Learner's Dictionaries
4. umpteen: American Heritage Dictionary of the English Language
5. umpteen: Collins English Dictionary
6. umpteen: Vocabulary.com
7. Umpteen, umpteen: Wordnik
8. umpteen: Cambridge Advanced Learner's Dictionary
9. umpteen: Wiktionary
10. umpteen: Webster's New World College Dictionary, 4th Ed.
11. umpteen: The Wordsmyth English Dictionary-Thesaurus
12. umpteen: Infoplease Dictionary
13. umpteen: Dictionary.com
14. Umpteen: Wikipedia, the Free Encyclopedia
15. umpteen: Rhymezone
16. umpteen: FreeDictionary.org
17. umpteen: Mnemonic Dictionary
18. umpteen: TheFreeDictionary.com

Slang (4 matching dictionaries)

19. umpteen: Green’s Dictionary of Slang
20. umpteen: English slang and colloquialisms used in the United Kingdom
21. umpteen: ESL Slang page
22. umpteen: Urban Dictionary

(Note: See umpteenth as well.)

Definitions from WordNet ( ) ▸ adjective:  innumerable but many Types: myriad, infinite, countless, endless, uncountable, numberless, more... ▸ Words similar to umpteen ▸ Usage examples for umpteen ▸ Idioms related to umpteen ▸ Wikipedia articles (New!) ▸ Popular nouns described by umpteen ▸ Words that often appear near umpteen ▸ Rhymes of umpteen ▸ Invented words related to umpteen