marked by unthinking boldness; with defiant disregard for danger or consequences; "foolhardy enough to try to seize the gun from the hijacker"; "became the fiercest and most reckless of partisans"-Macaulay; "a reckless driver"; "a rash attempt to climb the World Trade Center"
disapproval If you describe behaviour as foolhardy, you disapprove of it because it is extremely risky. When he tested an early vaccine on himself, some described the act as foolhardy. taking stupid and unnecessary risks = reckless