Green’s Dictionary of Slang

1. to consume a drink.

1904		Truth (Brisbane) 10 Apr. 5/1: A half-sovereign in the plunder being marked, and, added to the fact that the young half-a-crown a week had been lashing up a lot lately, led to his arrest.
2009		T. Black Gutted 237: I had a quarter of vodka in my inside pocket, cracked it open, tipped back a few mouthfuls. [...] ‘You’re not gonna lash that, are you?’ said Hod.

2. (Irish) to rain heavily [as if it is whipping you].

1982		(con. 1930s–50s) E. Mac Thomáis Janey Mack, Me Shirt is Black 91: It’s bloody well lashing cats and dogs.
1993		R. Doyle Paddy Clarke Ha Ha Ha 95: I thought [...] that it had stopped raining. But it hadn’t. It was lashing.
1994		P. Quigley Borderland 1343: It’s lashing rain out there.
1996		(con. 1970) G. Moxley Danti-Dan in McGuinness Dazzling Dark (1996) I iv: I remember my mother saying that every summer when she was small it was raining. Day in, day out. Lashing the whole time.
1996		(ref. to 1963) D. Healy Bend for Home 194: It was lashing.
2001		G. Coughlan Everyday Eng. and Sl. 🌐 Lashing (v): raining hard.
2009		E. Forbes Our Lady of Pain 241: Rain was lashing down when Donovan left Professor Spicer’s building.

3. (W.I.) of either gender, to have sexual intercourse, esp. in a vigorous manner.

1979		T. Rhone Old Story Time I i: So the ol’ careless boy them lash her, is so she breed.
2005		P. Howard Curious Incident of the Dog in the Nightdress 289: I’d fooken lash that Samantha Mumba.
2005		Jade LB Keisha the Sket (2021) 36: I gt lashed twice, gt a hubby an shanked sum1.
2021		P Howard Braywatch 180: ‘By the way, I lashed your mate Delma out of it in the gorden’.

4. (US) to urinate [fig. use of sense 1 above].

1964		in E. Cray Erotic Muse (1992) 30: My lady she was dressing, / Dressing for the ball, / When she saw the jolly tinker / Lashing piss against the wall.
1995		S. Moore In The Cut 98: I have new words for the dictionary. [...] to lash, to urinate.

5. (UK black) to mug, to steal from; thus lashing n., a street robbery.

1989		J. Morton Lowspeak 91: Lashing – a violent robbery.
2003		Music from the Corner ‘The Promise’ 🎵 In West End, lashing the tourists for a quick spend.

6. to discard, to get rid of.

2001

K. Sampson Outlaws (ms.) 119: I keep the free biro and lash the leaflet.