Green’s Dictionary of Slang

1. one who performs cunnilingus.

1929		G. Fass [play title; unpub.] The Muff Diver.
1930		D. Maurer ‘Schoonerisms’ AS V:5 391: muff-diver. A pervert of either sex who is addicted to cunnilinctus.
c.1935		‘Betty Co-Ed’ [comic] in B. Adelman Tijuana Bibles (1997) 57: Q: Whats the strip of skin between a woman’s cunt and ass hole for? A: A chin rest for muff-divers.
1942		in G. Legman Limerick (1953) 239: A muff-diver’s dream / Because he refused to let puss go.
1966		Trimble 5000 Adult Sex Words and Phrases.
1972		B. Hannah Geronimo Rex 250: Let me get on my muff-diver goggles.
1985		‘Jennifer Blowdryer’ Modern English 74: homosexual women (n): Slot Lickers, Carpet Chewers, Muff Divers.
1986		J. Ellroy Suicide Hill 134: ‘The rape guy turned out not to be a rape-o, more like a psycho muff diver. He did this rebop about being a shark, then went down on Chrissy's bush’.
1991		W.T. Vollmann Whores for Gloria 42: Jack said to Jimmy I could tell just by looking at you you’re a muff diver, I’m telling you Dinah is real good to eat out her pussy just pops and pops like popcorn.
1992		R.G. Barrett White Shoes 19: A bunch of men [...] wearing yellow Bondi shirts with ‘Mac’s Head Muff Divers Annual Tour of Duty’ stitched on the front pocket. ‘No Muff Too Tough’.
2001		(con. 1964–8) J. Ellroy Cold Six Thousand 242: ‘Dick Contino?’ ‘Muff-diver and gamble-o-holic. In hock to the Chicago Cartel.’.
2023		(con. 1962) J. Ellroy Enchanters 29: Eddie [Fisher] introduced his combo as the Four Muff Divers.

2. a lesbian.

1930		see sense 1.
1950		Goldin et al. DAUL 142/2: Muff diver. See Bumper.
1972		B. Rodgers Queens’ Vernacular 139: muff diver [duffer] cunnilinctrice, woman who orally gratifies her partner.
1997–2000		College Sl. Research Project (Cal. State Poly. Uni., Pomona) 🌐 Muff diver {vulgar} (noun) 1. A lesbian. 2. A guy that likes to eat at the ‘Y’. (girls genitalia).

3. a contemptible person.

1946

P. Bowman Beach Red 42: The one us boys got had a long vine tied to a clump of grass on one end and to a bush on the other. The little muff diver located himself in a tree in between.