Green’s Dictionary of Slang

lamp v.1

[? lam v.1 ]

1. to beat, to strike, to thrash.

[UK] in Jamieson Etym. Dict. Scot. Lang.
[UK]J. Morton Lowspeak 91: Lamp – 2. to hit in the face.
[UK]N. Griffiths Sheepshagger 240: Fuckin lucky there Llýr, I was just about to fuckin lamp yew one I was.
[UK]C. Brookmyre Be My Enemy 166: Energetically lamping Rory with a ‘Shut Up You Smug Tory Twat’ baseball bat.
[UK](con. 1980s) I. Welsh Skagboys 269: One ay these days the big felly’s gaunny turn roond n lamp that stroppy wee fucker.
[US]C. Black ‘Topless Vampire Bitches’ in C. Rhatigan and N. Bird (eds) Pulp Ink 2 [ebook] I swear if he changes his mind one more time I’m goonna fuckin’ lamp him!

2. (W.I.) to trick, to deceive.

[WI]cited in Cassidy & LePage Dict. Jam. Eng. (1980).