the.com/shag

means As a verb/noun it's blunt British slang for sex; as an adjective it describes a long, shaggy pile (carpet or hair) that looks pleasantly unkempt.

from The adjective traces back to Old English 'sceacga,' meaning a growth of hair or rough matted wool — the same root gives us the shaggy dog and, eventually, the shag haircut and that thick-pile 1970s carpet. The sexual sense of 'shag' as a verb emerged later, by the 18th-19th century, in British slang — its exact path is murky, but it likely grew from the same idea of rough, vigorous motion rather than from any tidy single source. One bird, the shag (a type of cormorant), gets its name from the same hairy-crested root, purely coincidentally riding along for the wordplay.