It of course could be 2 pieces of sesame seed bun with some cooked lamb in the middle like a sandwich and known as a lamb burger- However the far more common use for this term is a descriptive reference to insult those who attempt/ or are known to have sexual intercourse with sheep or lambs. Commonly conversationally in Derby in the Uk and the whole of Wales.
"I really can't believe what I read about that guy with the sheep in the field that's disgusting"
"Hey man I could have told you, he's been smashing those lamb burgers for some time Baaaaaaa!"
"Dude, too much.. That's sick and not in a good way"
"Hey man I could have told you, he's been smashing those lamb burgers for some time Baaaaaaa!"
"Dude, too much.. That's sick and not in a good way"
by Vegetablerightsandpeas July 28, 2016

An amputee ramming another person up their marmite motorway with their stump. "Fancy a bit of lamb shanking?"
by #angrygrowler May 8, 2014

by that one emo kid in class March 23, 2019

Person 1: Hey did you hear what Dan got upto last night?
Person 2: Hahaha, yeah. Him and Ashley, right?
Person 1: Yeah, he's such a lamb slayer.
Person 2: Hahaha, yeah. Him and Ashley, right?
Person 1: Yeah, he's such a lamb slayer.
by Vocabulary Genius Cass June 4, 2012

by masterofrpg March 30, 2004

by cdiamondz May 27, 2006

gay "metalcore" pop band, kids love to "mosh" and headbang with shaved heads to this product. see also mtv
by mathias February 16, 2005
