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4.
A best friend for life. A girl or guy, whom one is best friends with. Someone who you can trust and whom you love a lot, but as a friend. And only a friend.
This is my biffle Chelsea, we do everything together and have a lot in common. I love my biffle, she is my best friend for life. I would never want to lose my biffle,she is an amazing friend.
by Christiana Carrico November 02, 2007
 
1.
one's BFFL, or Best Friend For Life. it is supposed to be the opposite sex, whom one is JUST friends with, and wouldn't ever date. however many biffles become boyfriends, which really defeats the purpose. unlike best friends, you can only have ONE biffle.
"I heard you and Johnny have been hanging out a lot, are you dating?"

"No way, he's my biffle, duh."
by Britney Kay September 30, 2005
 
2.
From the acronym 'BFFL', which stands for 'best friends for life'.
He was acting like we were biffles, even though I hadn't heard from him in years.
by Hudson December 23, 2004
 
3.
Pronunciation: \'bih-full\
Function: noun
Etymology: from the internet slang term bffl (best friends for life)
April && Dilleh are biffles!! =]
by dilleh November 16, 2007
 
5.
a person's best friend
Zak and Christine are the best biffles alive.
by Christine February 08, 2005
 
6.
Pronounced "BEA-fle"

French word for dong slap.
composed of the words "Bite" (french slang for penis) and "Giffle" (french for slap).

The biffle is used on highly inebriated frenchmen as a show of male dominance always against the one receiving (le bifflé). The one initiating the dong slap is known as "le bifflard"
je lui ai mis une de ses biffles! elle s'en rappellera jusqu'à sa mort !

I gave her such a dong slap! She's going to remember it for the rest of her days!
by bigfg September 09, 2009
 
7.
Usually a great friend of the opposite sex who you can trust with your life. However, someone who is a biffle is not necessarily stuck in the "friend zone", as biffles often make the best couples. Often, a girl may instigate a biffle relationship as a way of flirting. It is customary to be protective and loyal to your Biffle.
"So is Johnny just your biffle?"

"Yeah, he's just my biffle.. for now..."

"Hey Danny, would you like to be my biffle?"
by KatFish21 August 30, 2012