We found 14 dictionaries that define the word at first:

General (12 matching dictionaries)

1. at first: Merriam-Webster
2. at first: Oxford Learner's Dictionaries
3. at first: Wordnik
4. at first: Cambridge Advanced Learner's Dictionary
5. at first: Wiktionary
6. At first, at first: Dictionary.com
7. at first: Rhymezone
8. at first: FreeDictionary.org
9. At first: TheFreeDictionary.com
10. at first: Longman Dictionary of Contemporary English

Business (1 matching dictionary)

11. at first: Legal dictionary

Miscellaneous (1 matching dictionary)

12. at first: Idioms

Definitions from WordNet (at first) ▸ adverb:  at the beginning ("At first he didn't notice anything strange") Opposite: initially Types: initially, to begin with, in the beginning, firstly, more... Phrases: at first blush, at first sight, at first glance, at first hand, love at first sight, more... ▸ Words similar to at first ▸ Usage examples for at first ▸ Idioms related to at first ▸ Wikipedia articles (New!) ▸ Words that often appear near at first ▸ Rhymes of at first ▸ Invented words related to at first