Definition of "scag"

scag

/skæɡ/

noun
countable and uncountable, plural scags
1. (slang, uncountable) Heroin.
  Quotations
  And I was snorting scag while other kids played tag
  1973, “Sport”, in Hustler's Convention, performed by Lightnin' Rod
  So goodbye Cocaine Carolina, you and I are through / I'm going back to Sandy Scag, she knows just what to do
  1975, David Allan Coe (lyrics and music), “Cocaine Carolina”, performed by Johnny Cash
  Mark: No. I'm off the scag. Ten days without the scag. And I'm going away.
  1996, Mark Ravenhill, Shopping and Fucking, Scene One
2. (slang, countable, derogatory, originally African-American Vernacular) A woman of loose morals.
3. (slang, countable, dated, US) A cigarette.
  Quotations
  “Then have a skag,” said I. / “’Twill make it seem like happier times, / You liked this brand, I understand.”
  1915, “The Doomsday Butt”, in The Cornhusker, page 458
  Awoke when our florescent lights came on and went outside to smoke a few scags before breakfast.
  1996, Paul Bunker, Keith Barlow, Bunker's War: The World War II Diary of Paul D. Bunker, page 134
verb
third-person singular simple present scags, present participle scagging, simple past and past participle scagged
1. (computing) To destroy the data on a disk, either by corrupting the file system or by causing media damage.