Definition from Wiktionary, the free dictionary
Alternative forms 
- Rhymes: -ʌŋ
Etymology 1 
mung (plural mungs)
Etymology 2 
Possibly from Mash Until No Good, or a self referencing acronym, Mung Until No Good. Rumored to have originated from one of the Massachusetts Institute of Technology computer groups in the 1970s or 1980s.
- (computing) To make repeated changes to a file or data which individually may be reversible, yet which ultimately result in an unintentional irreversible destruction of large portions of the original data.
- (by extension) to destroy