[verb] give moral or psychological support, aid, or courage to; "She supported him during the illness"; "Her children always backed her up" Synonyms:support
[verb] move backwards from a certain position; "The bully had to back down" Synonyms:back off, back down
[verb] establish as valid or genuine; "Can you back up your claims?" Synonyms:back
[verb] make a copy of (a computer file) especially for storage in another place as a security cop; "You'd better back up these files!"
[verb] become or cause to become obstructed; "The leaves clog our drains in the Fall"; "The water pipe is backed up" Synonyms:clog, choke off, clog up, congest, choke, foul
