Green’s Dictionary of Slang

lay up v.

1. (also lay to) to rest, to relax.

[US]C. Abbey diary 28 Apr. in Gosnell Before the Mast (1989) 30: I ‘Laid up’ last night sick. [Ibid.] 3 Aug. 65: We did nothing after 8 bells so I ‘laid to’ with a book.
[UK]Leicester Chron. 6 Nov. 9/1: About this time he had a very severe illness, but where he was ‘laid up’ in tramp’s parlance, is not known.
[UK]Sporting Times 1 Mar. 3/2: Billy Wright is laid up at the Grand, and I was paying a visit of sympathy.
[UK]Boy’s Own Paper 15 Dec. 168: We were told to lay up till further orders, and thought ourselves safe for the night.
[US]J. Lait ‘Omaha Slim’ in Beef, Iron and Wine (1917) 109: If ye wanna do a couple o’ overtime tricks ye kin lay up fer all winter.
[US]R. Lardner Big Town 45: I’d been laid up mean wile with the Scotch influenza.
[US]‘Boxcar Bertha’ Sister of the Road (1975) 160: She said she and a barber ‘laid up’ in one [i.e. a boxcar] the first time she took a man.
[Aus]K. Tennant Battlers 201: The Stray and Jimmy had explained to everyone that Snow had left them with a friendly family in Logan while she was laid up with some mysterious ailment.
[US] ‘The Junkie’ in D. Wepman et al. Life (1976) 101: I was laying up in my pad, no longer sad.
[US]C. Himes Blind Man with a Pistol (1971) 36: What’s unusual about a black brother stealing a whitey’s pants who’s laying up somewhere with a black whore?
[US]E. Torres Carlito’s Way 71: Come Sunday I lay up like a respectable citizen.

2. (US) to die.

[US]‘Mark Twain’ Life on the Mississippi (1914) 29: It’s all on account of the water the people drink before they laid up.

3. to live, to be in a place.

[US]S. Lewis Babbitt (1974) 159: Just because they happen to lay up in a big wad.
[US]A.J. Barr Let Tomorrow Come 149: There ain’t a real dick goin’ that can’t spot you after you lay up a few years in one o’ these places.

4. (US, also lie up) to hide, to take refuge.

[US]M.C. Sharpe Chicago May (1929) 88: If a man kicked free of America, he could lay up with Mr. Oakes.
[US]D. Runyon ‘The Three Wise Guys’ in Runyon on Broadway (1954) 404: The Dutchman [...] lays up in a town by the name of New Brunswick.
[UK]‘Charles Raven’ Und. Nights 12: He would [...] lie up somewhere, with that timeless patience which all great Creeps possess, until zero hour.
[US]R.R. Lingeman Drugs from A to Z (1970) 140: lay up Having acquired a large supply of drugs, to withdraw from hustling and lie about one’s room using the drugs, as in ‘I used the money to buy a big stash of heroin and decided to just lay up for the next couple of weeks’.
[US]J. Ellroy Brown’s Requiem 11: I laid up at another friend’s crib.
[US]G. Pelecanos Soul Circus 162: You can lay up here for a little while, I guess.

5. see lay back v.

In phrases

lay up in (v.)

(US black) of a man, to penetrate a woman.

[US]UGK ‘Like That’ [lyrics] I lay up in you bitch you gon’ cum.