goof

(noun) a man who is a stupid incompetent fool. Synonyms: fathead, goofball, bozo, jackass, goose, cuckoo, twat, zany.

(noun) a person who amuses others by ridiculous behavior. Synonyms: clown, buffoon, goofball, merry andrew.

(verb) commit a faux pas or a fault or make a serious mistake. Synonyms: drop the ball, sin, blunder, boob. Example: "I blundered during the job interview."