The knotty mess of hair at the back of a woman's head caused by being rubbed against the pillow during sex, or from her hair being grabbed by her partner during doggy-style sex.
'Ohh look at the state of Julie's hair. That shag-knot tells us what she was up to before she came into work today!'

'Sort your hair out Elaine. You've still got a shag-knot going on'
by Sidders02 March 8, 2021
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