Meaning

2 senses
  1. (slang)A black ski mask or balaclava.

  2. A person that is untrustworthy, selfish, deceitful and in some cases heartless.

Origin

Probably from shyst(er) + -y. Green's Dictionary of Slang suggests that the word is a blen

Probably from shyst(er) + -y. Green's Dictionary of Slang suggests that the word is a blend of shit + feisty or shicer (“a worthless person”) + feisty. The noun sense is a reference to the rapper Pooh Shiesty, known for wearing ski masks on stage.

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