What does the word jet mean?

Usage examples for jet

  1. A jet of brown gas was playing from it now. – Greylorn by John Keith Laumer
  2. Her pallor was interesting, her hair jet black, and her manners fascinating; but for all that I could never have worshipped at her shrine. – Fragments of an Autobiography by Felix Moscheles
  3. Evidently, Hank decided, all of this dozen- odd cluster of youngsters were connected with the jet- set underground. – Combat by Dallas McCord Reynolds