BFOS

Stands for Best Friend Out of Spite- Someone a person claims/pretends someone is their best friend when in reality their real best friend hasn't hung out with them as much as they used to and they're trying to make them jealous.

Friend 1: You're my best friend!

Friend 2: But I thought James was your best friend. You've known him your whole life. You've only known me for a week.
Friend 1: James used to be my best friend but he's not hanging out with me anymore, so you're my best friend now! Besides, he's stupid.
Friend 2: I'm just a BFOS, aren't I?

by Ashbuscus. November 19, 2017

BFO

"BFO" or "Blinding Flash of the Obvious" is when you suddenly realize how absurdly simple the answer to a problem or situation is.

I just had a "BFO", I am a Geek!!!

by Dale Sanford January 12, 2006

BFO

BIG FUCKIN Object

Did you see that BFO? Man I almost run into that BFO. Anything bigger then a car

by RangerNii March 25, 2010

BFO

"Boob Falling Out"
When your boobs are falling out of your shirt or dress

Jane needs to pull up her shirt she has a BFO!

by Thisismyusername111 August 03, 2010

BFO

BITCH FUCK OFF!!!!!!!

BFO and crawl back into your hole.

by 2345 cuppycake March 29, 2016

BFOS

Acronym for Boyfriend Freak Out Syndrome.

When you like someone, get to know them then freakout, run away (or hide yourself in the toilet), and/or do something stupid to sabotage your chances with a guy you like. Usually at a point when it is most important in getting a date, etc.

Friend: Why did you run into the toilet just as that guy was going to talk to you?

You: I dont know I guess BFOS got ahold of me.

by Freak out girl October 12, 2009

BFO

Boy Friend Obsessed: Used to describe when a person is spending most of their time with their boyfriend while neglecting their other friends. Also used to describe when a person brings their boyfriend around at all times and cannot do anything as an individual.

Jessica is acting so BFO I haven't seen her in a week!

by Shannanigans13 December 09, 2009