someone who is trigger-happy uses their gun too often and without thinking carefully.

The book's main character is a trigger-happy New York detective.

• spin wheels
• spin your wheels
• spirit moves
• spirit moves you
• spit and polish
• spit-and-sawdust
• spit blood
• spit nails
• split hairs
• split sides
• split sides laughing
• split the difference
• split your sides
• split your sides laughing
• spoiling for a fight
• spoil rotten
• spoil someone rotten
• sporting chance
• spread itself too thin
• spread like wildfire
• spread the word
• spread thin
• spread too thin
• spread wings
• spread yourself too thin