Tying a sock on a doorknob to signify to others that you are inside the room having sex. You do this as an international sign to say: do not enter. If you do, you will regret it and I will be embarrassed.
Sometimes called a doorsock
My roommate saw the sock on the doorknob, so they knew I was in there having fun with my partner.
by Strongly Opinionated Erin January 13, 2018
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Sock hanging from a doorknob

Sign indicating that the occupant of that room is engaged in self pleasure.
Sock hanging from a doorknob

(Younger student) just to make sure, you do know what it means when you see a sock hanging from the doorknob right?

(Older student) I have an idea

(Younger student) just knock and count to like ten and I’ll put it away .
by Rakis June 8, 2018
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