rack, v.² — Green’s Dictionary of Slang

rack v.²

1. (orig. US black) to go to sleep.

2000		(con. 1940s–60s) Décharné Straight from the Fridge Dad 151: Rack ’em back Pull up the covers and go to sleep.
2005		Prison Slang Mommyblogger mydogharriet.blogspot.com 23 Sept. 🌐 Its time to rack in and red tag until she can learn how to be on the one.

2. (US, also rack in) to sleep; thus racked out adj., asleep.

1967–8		Baker et al. CUSS 180: Rack [...] Rack it [...] Rack out [...] Rack, get [...] Rack, go Go to bed (not sexual).
1972		D. Jenkins Semi-Tough 127: Everybody else is still racked in and I guess I’m up early.
1975		G. Underwood ‘Razorback Sl.’ in AS L:1/2 54: rack ‘bed, go to sleep’.
1989		J. Doyle College Sl. Dict. 🌐 rack [U. of Oklahoma] to sleep.
1993		B. Moore Lex. of Cadet Lang. 291: rack [...] to sleep. As a verb the term is usally (to) rack out (occasionally also (to) rack over).

3. (also rack with) to seduce a woman, to make love.

1953		L. Durst Jives of Dr. Hepcat (1989) 8: Oh yes! In every park there will be sacks where you rackem back.
1978		R. Price Ladies’ Man (1985) 131: I know what I’m doing when I rack, but that night [...] I felt like a high school senior. I came right away.
1995		(con. 1985–90) P. Bourjois In Search of Respect 294: ‘She ended up being Ray’s woman.’ [...] ‘They used to rack in them days.’.

rack date (n.)

a seducible female.

1977

Eble Campus Sl. Apr. 3: rack date – a female who can be easily persuaded into bed.

rack out (v.)

(US) to fall asleep, to go to bed.

1960		‘Lord & Marshall’ So Willing 78: [T]he clock on the table beside the bed said seven-thirty. He’d been racked out for more than twelve hours.
1975		G. Underwood ‘Razorback Sl.’ in AS L:1/2 64: I’m going to go to my room and rack out.
1983		R. Price Breaks 117: Usually they left their door ajar when they racked out.
1988		Eble Campus Sl. Oct.
2004		J. Ellroy ‘Jungletown Jihad’ in Destination: Morgue! (2004) 375: Rape-os come out comatose and rack out too ratched to rape.