back up

In information technology, backup refers to making copies of data so that these additional copies may be used to restore the original after a data loss event. These additional copies are typically called "backups." Backups are useful primarily for two purposes. The first is to restore a computer to an operational state following a disaster (called disaster recovery). The second is to restore small numbers of files after they have been accidentally deleted or corrupted. Backups are typically that last line of defense against data loss, and consequently the least granular and the least convenient to use.
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Verb
1. give moral or psychological support, aid, or courage to; "She supported him during the illness"; "Her children always backed her up"
(synonym) support
(hyponym) sponsor
(derivation) backing, backup, championship, patronage
2. move backwards from a certain position; "The bully had to back down"
(synonym) back off, back down
(hypernym) withdraw, retreat, pull away, draw back, recede, pull back, retire, move back
3. establish as valid or genuine; "Can you back up your claims?"
(synonym) back
(hypernym) confirm, corroborate, sustain, substantiate, support, affirm
4. make a copy of (a computer file) especially for storage in another place as a security cop; "You'd better back up these files!"
(hypernym) copy, re-create
(derivation) backup, computer backup
(classification) computer, computing machine, computing device, data processor, electronic computer, information processing system
5. become or cause to become obstructed; "The leaves clog our drains in the Fall"; "The water pipe is backed up"
(synonym) clog, choke off, clog up, congest, choke, foul
(hypernym) obstruct, obturate, impede, occlude, jam, block, close up
(hyponym) gum up
(derivation) backup

(1) When bond yields rise and prices fall, the market is said to back-up. (2) When an investor swaps out of one security into another of shorter current maturity, he/she is said to back up.

To kill headway; to flank or twist tow at foot of crossing or head of bend. (TNDOT1)

In cartography, an image printed on the reverse side of a map sheet already printed on one side. Also the printing of such images. 1/2/73

En cartographie, image imprimée au verso d'une carte déjà imprimée au recto. Désigne également l'impression de ces images. 1/2/73