hothead

noun

Etymology: From hot + head. Compare English hotbrain (“a hothead”); Middle English hot-heorte, hat-heorte (“anger”), Old English hātheort (“furious, angry, irascible, passionate, ardent”, literally “hot-heart”).

1. One who becomes angry easily or goes in search of arguments or fights.

   “The club was full of eager young hotheads who never seemed to be able to agree on anything.”

2. One who reacts quickly and without thinking carefully first.

   “Someone get this hothead out of here before he does some damage.”