The girl that your best friend is dating, who is obligated to be a total bitch because of some subliminary life cliche. She will be clingy, possessive, and controlling, giving you little to no bro-time.

You and other friends will be forced to accept her into your social circle, but will talk mass loads of shit on her whenever you get the chance.
Your friend and your best friend's girlfriend-

"Hey bro, you still drinking with us this weekend?"

"Can't dude, I have to hang out with Carly."

"But broski, you've hung out with her everyday for six days now- Whatever, just bring her with."

"She doesn't want too, dude, sorry."
by Austavious Rex March 30, 2010
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a stupid comeback phrase that's used for virtually everything, even if it doesn't make any sense whatsoever
Friend #1: dude! i saw your mom last night! she was hot!
Friend #2: your best friend's sister!
Friend #!: you have a sister!?

dude: what happened last night!?
dude 2: your best friend's sister!
dude: shut up!
by dawg69 June 21, 2009
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The hardest, yet most satisfying thing in the whole entire world.
Being in love with your best friend is never having to worry about anything except everything.
by F.R.I.E.N.D.S February 25, 2014
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(n.) a new holiday that falls on National Best Friend Day each year, appropriately observed by licking your best friend to show your love and appreciation, possibly derived from the affectionate behavior of the dog, man's best friend. It is meant to be a prank that is both annoying yet endearing.
Johnson: Did you know today is Lick Your Best Friend Day?

Bob: *lick*
Johnson: Y..you're my best friend too... :')
by bugajoob June 08, 2014
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