backup

Etymology

From back + up.

noun

1. A reserve or substitute.
   If the goalkeeper is injured, we have a backup.
2. (computing) A copy of a file or record, stored separately from the original, that can be used to recover the original if it is destroyed or damaged.
   After the power failure, we had to restore the database from backup.
3. An accumulation of material caused by a (partial) obstruction or (complete) blockage of the flow or movement of the material, or an accumulation of material that causes an overflow due to the flow being greater than the maximum possible flow.
   The accident caused a mile-long backup on the highway.
   The blockage caused a backup in the plumbing.
4. (law enforcement) reinforcements
   He's got a gun! You'd better send for backup.
   Shaman: My patience is tested, but Uvenk invokes correctly. Grunt, who is your krantt? Your allies willing to kill and die on your behalf? Shepard: How is a candidate tested if he brings backup on his Rite of Passage? Shaman: Not every krogan can be the strongest warrior, but each must inspire his peers to battle at his side. Shaman: If the ones who know you best can find nothing worthy in you, you should wander the wastes and die alone before you weaken my clan. 2010, BioWare, Mass Effect 2 (Science Fiction), Redwood City: Electronic Arts, →OCLC, PC, scene: Tuchanka

adj

1. Standby, reserve or extra.
   I am only a backup player.
2. (computing) That is intended as a backup.
   Make a backup copy of that file.
3. Supporting, reinforcing; (music) of or related to accompaniment

verb

1. (computing, nonstandard) Alternative form of back up
   We have two methods for backupping: the first one is writing the contents of disks onto magnetic tapes and the other is making a copy of the contents of disks on the disk of the mainframe computers of the laboratory. 1989, CERN, page 235