Verb

1. to begin a race too soon, before the starting gun goes off
2. to act or begin too soon or without due caution

   "Shoe designers jump the gun on priorities; use substitutes while leather is available" - New York Times, 1942

   Don't you think it is jumping the gun to report this without verifying it?

3. (investing) to trade securities based on information that is not yet public; to trade on inside information