From Longman Dictionary of Contemporary Englishshagshag1 /ʃæɡ/ (also shagpile /ˈʃæɡpaɪl/) adjective → shag carpet/rugshagshag2 noun 1 [countable] British English informal not politeSEX/HAVE SEX WITH an act of having sex with someone2 [countable]HBB a large black sea bird3 [uncountable]DFT strong-tasting tobacco with thick leaves cut into small thin pieces
Examples from the Corpus
shag• I don't know where they are - they've probably gone upstairs for a shag.• Red-throated divers and shags feed a lot on young saithe and also on sand-eel.shagshag3 verb (shagged, shagging) [intransitive, transitive] British English informal not polite SEX/HAVE SEX WITHto have sex with someone→ See Verb tableExamples from the Corpus
shag• All she ever thinks about is shagging.• To hear him talk, you'd think he's shagged every woman in town!Origin shag2 Old English sceacga shag3 (1900-2000) Origin unknown 