characterized by undue haste and lack of thought or deliberation; "a hotheaded decision"; "liable to such impulsive acts as hugging strangers"; "an impetuous display of spending and gambling"; "madcap escapades"; (`brainish' is archaic)
disapproval If you refer to someone as a hothead, you are criticizing them for acting too quickly, without thinking of the consequences. someone who does things too quickly without thinking