foolhardy
1. [ adjective ] marked by unthinking boldness; with defiant disregard for danger or consequences
Synonyms: reckless rash
Examples:

"foolhardy enough to try to seize the gun from the hijacker" "became the fiercest and most reckless of partisans"-Macaulay "a reckless driver"

Related terms: bold
Similar spelling:   foulard