Green’s Dictionary of Slang

wee n.

also wee-wee
[? juv. mispron. of ‘u-ween’ (urine) or var. pee n.1 (1)]

(mainly juv.) urine, urination.

[UK]Partridge DSUE (1984) 1315/1: late C.19–20.
[US] joke cited in G. Legman Rationale of the Dirty Joke (1972) I 303: Wee-wee my ass! Where the hell is the nearest whore-house!
[NZ]N. Hilliard Maori Girl 14: Netta’s rude. She said wee-wee.
[Aus]J. Hibberd Dimboola (2000) 77: Mummy, I want to have a wee.
[UK]A. Ayckbourn Joking Apart I i: Christopher did a wee-wee in the fireworks.
[Ire]J. Morrow Confessions of Proinsias O’Toole 40: We’ll have a wee and then go on to my place for coffee.
[UK]P. Reading 5x5x5x5x5 1v: He’s just sunk six pints [...] and he needs a wee.
[UK](con. 1964) P. Theroux My Secret Hist. (1990) 252: Doing wee-wee and poo-poo on the sidewalk.
[UK]G. Burn Happy Like Murderers 166: A flat that smelled of urine. Dettol and wee.
[UK]Guardian G2 15 Sept. 22: The guy was actually having a wee-wee at the table.
[UK]K. Waterhouse Soho 172: I’d just come down here for a little wee-wee, because I suffer from a weak bladder.
[UK]H. Mantel Beyond Black 206: I tested my wee and the line’s gone blue.
[Aus]T. Spicer Good Girl Stripped Bare 97: It makes me laugh so hard a bead of wee comes out.
[Aus]G. Gilmore Base Nature [ebook] [T]apping his hands against his thighs like a little boy wantign a wee-wee.

In compounds

wee-wee place (n.)

a lavatory.

[UK]G. Kersh Fowlers End (2001) 192: Do you mind terribly, old thing, if I use your wee-wee place?
M. Lowenfeld Play in Childhood 225: Then he asked for the ‘wee-wee place.’ He tried to lift the seat, but as it was stiff he could not do so.

In phrases

do wee-wee(s) (v.) (also do wi-wis, make wee-wee)

to urinate.

[Ire]J.P. Donleavy Ginger Man (1958) 187: If you’ll excuse me for a moment, I must make wee wee.
[US]Baker et al. CUSS 220: Weewees, do Urinate.
[US]H. Gould Fort Apache, The Bronx 174: Can I make weewee first?
[UK]R. McGough An Imaginary Menagerie 42: Kiwis / do wiwis / from spectacular heights.
[US]S. Morgan Homeboy 5: A plaster toddler making weewee in a giant seashell.
[Aus]Penguin Bk of More Aus. Jokes 83: Next time you want to do wee-wees, don’t use that word.
P. Breinburg Instead of Roses and Rings 30: No one could do wee-wees without their wee-wee thing, as the little boys secretly called it.
[US]S. King Finders Keepers (2016) 141: I’ll watch while you make wee-wee in the little plastic cup.
poor as wee-wee (adj.) [var. piss-poor under piss- pfx]

(N.Z.) unacceptable, second rate.

[NZ]G. Slatter Pagan Game (1969) 159: For crying out loud, said Eric. Can’t we change the subject? I think it’s poor as wee-wee to be talking about football all the time.