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

Derived forms: jumped the gun

• threadlike
• threads
• threadworm
• thready
• threap
• threat
• threaten
• threatened
• threatened abortion
• threatening
• threateningly
• three
• three day eventing
• three hundred
• Three Kings' Day
• three sheets to the wind
• three times
• three-bagger
• three-banded armadillo
• three-base hit
• three-card monte
• three-centered arch
• three-cornered
• three-cornered leek
• three-d