We found 19 dictionaries that define the word fastest:

General (13 matching dictionaries)

1. fastest: Merriam-Webster
2. fastest: Collins English Dictionary
3. fastest: Vocabulary.com
4. Fastest, fastest: Wordnik
5. fastest: Cambridge Advanced Learner's Dictionary
6. fastest: Wiktionary
7. Fastest, fastest: Dictionary.com
8. fastest: Cambridge Essential American English Dictionary
9. Fastest (film), Fastest: Wikipedia, the Free Encyclopedia
10. fastest: Rhymezone
11. fastest: FreeDictionary.org
12. fastest: Mnemonic Dictionary
13. fastest: TheFreeDictionary.com

Business (1 matching dictionary)

14. fastest: Legal dictionary

Computing (1 matching dictionary)

15. fastest: Encyclopedia

Medicine (2 matching dictionaries)

16. fastest: Merriam-Webster Medical Dictionary
17. fastest: Medical dictionary

Miscellaneous (1 matching dictionary)

18. fastest: Idioms

Slang (1 matching dictionary)

19. fastest: Urban Dictionary

(Note: See fast as well.)

Definitions from Wikipedia (Fastest) ▸ noun:  a model-based testing tool that works with specifications written in the Z notation. ▸ noun:  a documentary film about Grand Prix motorcycle racing, MotoGP. Opposite: slowest Types: land, sea, air, more... Phrases: fastest growing, fastest mile, Fastest animals, The World's Fastest Indian, Fastest recorded tennis serves, more... Colors:     red,     silver,     black,     blue,     yellow, more... ▸ Words similar to fastest ▸ Usage examples for fastest ▸ Idioms related to fastest ▸ Wikipedia articles (New!) ▸ Popular adjectives describing fastest ▸ Words that often appear near fastest ▸ Rhymes of fastest ▸ Invented words related to fastest