Green’s Dictionary of Slang

loopy adj.

also loop-o, loopy-loo
[? Scot. loopy, cunning]

1. (orig. naut.) eccentric, crazy.

[UK]N&Q 12 Ser. IX 347: Loopy. Daft; silly; mentally deficient.
[UK]D.L. Sayers Nine Tailors (1984) 253: You’ll think I’m loopy, but I tell you that bell was alive.
[UK]J. MacLaren-Ross ‘Y List’ Memoirs of the Forties (1984) 253: ‘He’s loopy! Lock him up!’ ‘Fetch a strait jacket!’.
[UK]C. Harris Three-Ha’Pence to the Angel 35: Saturd’ys you’d think they’d all gorn loopy-loo. And fights in the road.
[US](con. 1943) A. Myrer Big War 126: Don’t mind me. I’m getting loop-o.
[UK]Willans & Searle Complete Molesworth (1985) 291: Most just sit there with their mouths open looking loopy.
[US]N. Spinrad Bug Jack Barron 23: We both know he’s not that loopy.
[UK]A. Sillitoe Start in Life (1979) 84: I must have been loopy to want to do a thing like that.
[UK]J. Sullivan ‘Wanted’ Only Fools and Horses [TV script] This Blossom person is completely loopy you know!
[Aus]J. Byrell (con. 1959) Up the Cross 16: This loopy ear-bashing charlie.
[US]G. Tate ‘Marc Anthony Thompson’ in Flyboy in the Buttermilk (1992) 118: His lyrics written with literate, loopy, and socially conscious adults in mind.
[Aus]R.G. Barrett Wind & Monkey (2013) [ebook] I’ll try and slip her poor, loopy cousin a few bucks.
[UK]Observer Rev. 17 Oct. 10: Was Mrs Thatcher loopy and is it true her cronies still call her Prime Minister, Campbell wanted to know.
[US]C. Hiaasen Skinny Dip 193: Chaz wondered if the medicine patches were making Tool loopy.
[UK]R. Milward Apples (2023) 23: Driving aimlessly round [...] with him on loopy pills.
[US]‘Jack Tunney’ Split Decision [ebook] You got knocked loopy. Maybe I wasn’t watching that part.
[UK]J. Fagan Panopticon (2013) 62: Some loopy teacher was fostering me.
Skepta ‘Corn on the Curb’ 🎵 My niggas violent, my niggas loopy.
[US](con. 1962) J. Ellroy Enchanters 180: ‘Your loopy book The Sexual Criminal’.
[UK]J. Meades Empty Wigs (t/s) 854: [The book] was dotty. It was dangerously deranged. Really loopy.

2. obsessed with, mad about.

[US]J. Wambaugh Golden Orange (1991) 247: I don’t want you screwin me up jist because you gone loopy over some little squeeze.
[UK]Observer Screen 9 Apr. 6: The boys who have written it are as loopy about music as Nick is.
[UK]J. Joso Soothing Music for Stray Cats 107: The French are fucking loopy about her.
[US]‘Jack Tunney’ Split Decision [ebook] The only thing I’m loopy about is you, doll.

3. drunk or drugged.

[US]C. Hiaasen Stormy Weather 283: Snapper was loopy on Midols, Johnnie Walker and pure criminal adrenaline.
[US]J. Stahl Plainclothes Naked (2002) 297: They were both so loopy by then, he pulled down his pants.
[US]G.M. Graff Watergate XXX: Nixon drank too much and couldn’t hold his alcohol [...] just a drink or two could make him loopy.

4. unconscious.

[US]J. Ridley What Fire Cannot Burn 297: She’d taken a blow to the head [...] Probably, she’d been loopy only a short time.

In phrases

off one’s loop (adj.)

eccentric, mad.

[UK]J. Cary Horse’s Mouth (1948) 43: What are you talking about now. I declare you’re off your loop.
up the loop (adj.)

insane, eccentric.

H. Champion ‘Good Old Yorkshire Pudding’ [monologue] They maid a raid upon the soup, / Drove the shopman up the loop.
[UK]E. Pugh Punch and Judy 9: Up the loop. Barmy. Off their rocker. You know.
[UK]J. Franklyn Cockney 288: A variant of up the pole is up the loop, which gives rise to loopy.