We found 12 dictionaries that define the word pessimists:

General (8 matching dictionaries)

1. pessimists: Merriam-Webster
2. pessimists: Collins English Dictionary
3. pessimists: Vocabulary.com
4. Pessimists, pessimists: Wordnik
5. pessimists: Cambridge Advanced Learner's Dictionary
6. pessimists: Wiktionary
7. pessimists: Cambridge Essential American English Dictionary
8. pessimists: TheFreeDictionary.com

Business (1 matching dictionary)

9. pessimists: Legal dictionary

Computing (1 matching dictionary)

10. pessimists: Encyclopedia

Medicine (2 matching dictionaries)

11. pessimists: Merriam-Webster Medical Dictionary
12. pessimists: Medical dictionary

(Note: See pessimist as well.)

Definitions from Wiktionary (pessimist) ▸ noun:  Someone who habitually expects the worst outcome; one who looks on the dark side of things. ▸ Also see pessimist ▸ Words similar to pessimists ▸ Usage examples for pessimists ▸ Idioms related to pessimists ▸ Wikipedia articles (New!) ▸ Popular adjectives describing pessimists ▸ Words that often appear near pessimists ▸ Rhymes of pessimists ▸ Invented words related to pessimists