What does the word trigger mean?

Usage examples for trigger

  1. To launch the spear, or to touch the trigger, only remains. – A Complete Account of the Settlement at Port Jackson by Watkin Tench
  2. He trained the heat- gun on the second leg on the same side and pressed the trigger. – The Wealth of Echindul by Noel Miller Loomis
  3. Or some particular scene may trigger a complete memory return. – Monkey On His Back by Charles V. De Vet