Green’s Dictionary of Slang

1. (US campus) a fool.

1924		‘Digit’ Confessions of a Twentieth Century Hobo 175: To this day I am in doubt whether that man is more goofie than cootie or more cootie than goofie.
1927		H. Dignowity in Dobie Texas and Southwestern Lore 101: Other ‘slowpokes’ are called ‘Goofy’.
1932		J.L. Kuethe ‘Johns Hopkins Jargon’ in AS VII:5 332: goofy — n. — a stupid or crazy person.
1944		J.M. Inks diary Eight Bailed Out (1954) 29 July 37: The thin one, ‘Goofy,’ and our interpreter, ‘Jughead.’ The names fit.
1953		‘John Eagle’ Hoodlums (2021) 59: ‘Day-dreaming, goofy?’ asked Martin.

2. (US black gang) one who poses as the member of a gang.

2016

F. Stuart ‘Dispatches from the Rap Wars’ in chicagomag.com 🌐 goofy or lame Someone who pretends to be a violent gang member, often online, but is not.

3. see goof pill n.