Jet1, n.
n. [Written also jet, jayet.] [Fr. jayet, jaiet, jayet, from Lat. gagates, Gr. γαγάτης, λίθος γαγάτης, so called from Gagæ or Gagæ, a town and river in Lycia.] (Min.) A variety of lignite, of a very compact texture, and velvet-black color, susceptible of a good polish, and often wrought into toys, buttons, mourning jewels, and the like. Dana.