What is Sly Sign?
1.
When you put your middle finger up to somebody behind an opaque object (predominantly a door), releasing anger but not getting into trouble. Usually used by young teens, aimed at parents.
"My mom was being so annoying... so i sly signed her through the door when i left the room."
"No way dude!"
See
Random Words:
See unavailable, error, server
7.
(v.i.) Out to lunch; not having it together; acting in a stupid way. Typically derogatory.
Derivation: ..
