Green’s Dictionary of Slang

1. (UK Und.) one who hides in order to spy on others.

1618		Fletcher Loyal Subject IV iv: Take heed of bo-peep with your pate, your pate sir, I speak plain language now.
c.1786		Grose Classical Dict. of the Vulgar Tongue ms. additions n.p.: Bo-peep, One who sometimes hides himself, and sometimes appears publically abroad, is said to play at Bo-peep. Also one who lies Perdue, or on the Watch.
1788, 1796		Grose Classical Dict. of the Vulgar Tongue (2nd, 3rd edn).
1811		Lex. Balatronicum.
1823		Egan Grose’s Classical Dict. of the Vulgar Tongue.

2. sleep, also adj. (see cite 1912) [strengthened by rhy. sl.].

[1727		Swift ‘Cantata 1’ in Chalmers Eng. Poets XI (1810) 464/1: Now sweep, sweep the deep. See Celia, Celia dies, Weeping sleep, sleeping weep, Weeping sleep, bo peep, bo peep].
1880		D.W. Barrett Life and Work among Navvies 43: When a man is ready to retire to rest, he will inform his mates, ‘That he’s done his lot for the day, and is goin’ to lay his pen’oth o’ bread (head) on the weeping-willow (pillow), and do a little bo-peep (sleep)’.
1910		Eve. Teleg. (Dundee) 3 Aug. 4/1: So he goes back to his 'Charlie Wiggins' (diggings), winds up his 'three of Scotch' and after blowing the 'Harry Randle' out, he jumps into 'traitor's head' and is soon 'bo-peep'.
1912		Sport (Adelaide) 7 Sept, 14/2: They Say [...] That Lardy M. did not set the alarm, and was boo-peep [sic] when the drag left .
1932		‘P.P.’ Rhy. Sl. 11: Stick yer ‘lump of lead’ on the ‘tit-willow’ and ’ave a bo-peep, ’cos yer ‘elephants’.
a.1945		L. Payne private coll. n.p.: Sleep Bo Peep.
1960		J. Franklyn Dict. of Rhy. Sl.
1960, 1975		Wentworth & Flexner DAS.
1972		Dodson & Saczek Dict. of Cockney Rhy. Sl.
1999		R. Walton ‘Cockney Jack’ 🌐 Cockney Jack woke from his Bo-peep.
2002		M. Coles More Bible in Cockney 45: While I was ’aving a little Bo Peep, me stop-and-start was well awake.

3. a look, a ‘peep’; also as v.; often in phr. go for a bo-peep [strengthened by rhy. sl.].

1932		I.L. Idriess Flynn of the Inland 212: I reckoned th’ sun was getting up on th’ wrong side so I crawled out to bo-peep.
1940		F. Sargeson ‘A Man & his Wife’ Man and His Wife (1944) 76: Once they were a bit stonkered the boys would want to have a bo-peep at the bird while he was asleep.
1948		I.L. Idriess Opium Smugglers 252: Here, take a bo-peep at this!
1959		D. Niland Gold in the Streets (1966) 166: Wouldn’t mind having a bo-peep at that.
1963		A.E. Farrell Vengeance 53: I had a bo-peep at ’em meself.
1963–74		B. Humphries Barry McKenzie [comic strip] in Complete Barry McKenzie (1988) 23: Did yous get a bo peep at them pom’s faces.
2002		B. Kirkpatrick Wicked Cockney Rhy. Sl.

4. (US gay) in pl., the eyes.

1949		I.L. Idriess One Wet Season 180: All they had to do [...] was to keep their ‘bo-peeps’ well and truly on Maitland Buckle.
1972		B. Rodgers Queens’ Vernacular 36: bo-peeps eyes ‘Just focus your bo-peeps on that!’.

5. (US gay) dark glasses.

1972		B. Rodgers Queens’ Vernacular 117: sunglasses [...] tinted bo-peeps (rare).
1989–2003		R.O. Scott Gay Sl. Dict. 🌐.