mung
     n : erect bushy annual widely cultivated in warm regions of
         India and Indonesia and United States for forage and
         especially its edible seeds; chief source of bean sprouts
         used in Chinese cookery; sometimes placed in genus
         Phaseolus [syn: {mung bean}, {green gram}, {golden gram},
          {Vigna radiata}, {Phaseolus aureus}]
Source: WordNet® 2.0

mung /muhng/ vt. [in 1960 at MIT, `Mash Until No Good'; sometime after
   that the derivation from the {{recursive acronym}} `Mung Until No Good'
   became standard; but see {munge}] 1. To make changes to a file, esp.
   large-scale and irrevocable changes. See {BLT}. 2. To destroy, usually
   accidentally, occasionally maliciously. The system only mungs things
   maliciously; this is a consequence of {Finagle's Law}. See {scribble},
   {mangle}, {trash}, {nuke}. Reports from {Usenet} suggest that the
   pronunciation /muhnj/ is now usual in speech, but the spelling `mung' is
   still common in program comments (compare the widespread confusion over
   the proper spelling of {kluge}). 3. In the wake of the {spam} epidemics
   of the 1990s, mung is now commonly used to describe the act of modifying
   an email address in a sig block in a way that human beings can readily
   reverse but that will fool an {address harvester}. Example:
   johnNOSPAMsmith@isp.net. 4. The kind of beans the sprouts of which are
   used in Chinese food. (That's their real name! Mung beans! Really!)

   Like many early hacker terms, this one seems to have originated at
   {TMRC}; it was already in use there in 1958. Peter Samson (compiler of
   the original TMRC lexicon) thinks it may originally have been
   onomatopoeic for the sound of a relay spring (contact) being twanged.
   However, it is known that during the World Wars, `mung' was U.S. army
   slang for the ersatz creamed chipped beef better known as `SOS', and it
   seems quite likely that the word in fact goes back to Scots-dialect
   {munge}.


Source: The Jargon File