[1] : The Collaborative International Dictionary of English v.0.48

backup \back"up\, n.
   1. anything kept in reserve to serve as a substitute in case
      of failure or unavailability of the normal or primary
      object; -- used for devices, plans, people, etc. also used
      attributively; as, there was no backup for the electrical
      supply; a backup motor; a backup generator.
      pjc

   2. music a musician or group of musicians accompanying a
      soloist, whether vocalists or instrumentalists.

   syn: accompaniment. pjc

   3. a person or group of persons serving as reinforcement for
      another or others; as, the policeman called for backup
      when he was fired on.
      pjc

   4. an accumulation, overflow, or reverse flow in traffic or
      a liquid flow system caused by a stoppage or other
      malfunction.
      pjc

   5. computers a copy of a program or data from a computer
      onto a data-storage medium, usually one that may be
      removed to safe storage at a distance from the computer;
      it is used to preserve data for use in the contingency
      that the original data on the computer may be lost or
      become unusable. a backup that is removed from the
      building housing the computer system to provide
      protection against loss of data in a disastrous event such
      as a fire is called off-site backup. also used
      attributively; as, backup copy.
      pjc

   6. computers the act or process of creating a backup5;
      as, they performed a full system backup every weekend.
      pjc backward

[2] : WordNet (r) 2.0

backup
     n 1: an accumulation caused by clogging or a stoppage; "a traffic
          backup on the main street"; "he discovered a backup in
          the toilet"
     2: someone who takes the place of another as when things get
        dangerous or difficult; "the star had a stand-in for
        dangerous scenes"; "we need extra employees for summer
        fill-ins" syn: stand-in, substitute, relief, reliever,
         backup man, fill-in
     3: a subordinate musical part; provides background for more
        important parts syn: accompaniment, musical
        accompaniment, support
     4: computer science a copy of a file or directory on a
        separate storage device; "he made a backup in case the
        original was accidentally damaged or erased" syn: computer
        backup
     5: the act of providing approval and support; "his vigorous
        backing of the conservatives got him in trouble with
        progressives" syn: backing, championship, patronage
see also:
stand-in substitute relief reliever backup man fill-in 
accompaniment musical accompaniment support computer backup backing 
championship patronage 

[3] : Moby Thesaurus II by Grady Ward, 1.0

104 moby thesaurus words for "backup":
   about-face, about-turn, advocate, agent, alter ego, alternate,
   alternative, amicus curiae, analogy, attorney, back track,
   back trail, backing, backing off, backing out, backing up,
   backup man, champion, change, changeling, comparison, copy,
   counterfeit, deputy, double, dummy, equal, equivalent, ersatz,
   exchange, executive officer, exponent, fake, figurehead, fill-in,
   ghost, ghostwriter, imitation, lieutenant, locum, locum tenens,
   makeshift, metaphor, metonymy, mock, next best thing, paranymph,
   personnel, phony, pinch, pinch hitter, pleader, procurator,
   provisional, proxy, relief, replacement, representative, reserve,
   reserves, reversal, reverse, reversing, reversion, right-about,
   right-about-face, ringer, second in command, second string,
   secondary, sign, spare, spares, stand-in, stopgap, sub,
   substituent, substitute, substitution, succedaneum, superseder,
   supplanter, surrogate, swingaround, symbol, synecdoche, temporary,
   tentative, third string, token, turnabout, turnaround, understudy,
   utility, utility man, utility player, vicar, vicar general,
   vicarious, vice, vice-president, vice-regent, vicegerent,
   volte-face

[4] : The Free On-line Dictionary of Computing (27 SEP 03)

backup
     
         sometimes "back up" when used as a verb a
        spare copy of a file, file system or other resource for use in
        the event of failure or loss of the original.
     
        the term is most commonly used to refer to a copy of all the
        files on a computer's disks which is made periodically and
        kept on magnetic tape or other removable medium also called
        a "dump".
     
        this essential precaution is neglected by most new computer
        users until the first time they experience a disk crash or
        accidentally delete the only copy of the file they have been
        working on for the last six months.
     
        ideally the backup copies should be kept at a different site
        or in a fire safe since, though your hardware may be insured
        against fire, the data on it is almost certainly neither
        insured nor easily replaced.
     
        see also differential backup, incremental backup, full
        backup.  compare archive.
     
        2003-06-22
     
     
see also:
disks magnetic tape dump disk crash differential backup incremental backup 
full backup archive 

Backup >> B Words
Backup, definition of term: Backup
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