We found 4 dictionaries that define the word to back up:

General (4 matching dictionaries)

1. to back up: Wordnik
2. To back up: Dictionary.com
3. to back up: FreeDictionary.org
4. To back up: TheFreeDictionary.com

Phrases: to back something up, lots of information to back up, to get back up, to back you up, to bring back up an idea, more... ▸ Words similar to to back up ▸ Usage examples for to back up ▸ Idioms related to to back up ▸ Wikipedia articles (New!) ▸ Words that often appear near to back up ▸ Rhymes of to back up ▸ Invented words related to to back up