When a friend, or in some cases, somebody you don't even know hugs you at inappropriate and stupid times.
"Hmm... I can't find my pen"

*Gets hugged from his friend*

"Erm... what are you doing?"

"Just want to let you know I'm here for you in this hard time"

"Dude, get off me! You've got a bad case of Inappropriate Hug Syndrome!"
by drnick928 August 20, 2011
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