English dictionary

back up meaning and definition

BACK UP verb

Definition of back up (verb)

  1. give moral or psychological support, aid, or courage to
    • "She supported him during the illness"; "Her children always backed her up"
    • synonyms: support
  2. move backwards from a certain position
  3. establish as valid or genuine
    • "Can you back up your claims?"
    • synonyms: back
  4. make a copy of (a computer file) especially for storage in another place as a security copy
    • "You'd better back up these files!"
  5. become or cause to become obstructed
Source: Princeton University Wordnet