BSI 

Short for Batshit Insane i.e. beyond crazy

see: Batshit Insane or Bat Shit Insane

Person #1 "I just saw some chick take her clothes off and run down the street naked"

Person #2 "She must be BSI"

BSI by BSI Observer June 4, 2009

bsi 

Stands for "bull shit industries". The headquarters for the company is based right on top of gunnersbury underground station, but surprisingly, know really knows. They're most known for their blatant disregard for customers' needs and it's outright stupidity.

"Ah, s car's broken down, I'm calling bsi"
*rings them up*
"Okay, my car's broken down-"
"*in a bad indian accent* helo wood u like a banana?"
"Man. This some more bull shit."

bsi by Punjabi Peanut May 23, 2023

BSI 

Short for Bunny Smiles Inc, a fictional corporation that is the main focus of a fnaf inspired web sieries Walten File

BSI is planning to open a new attraction sometime this summer.

Here at BSI we bring our sincerest apologies.

BSI by ExhibitHumanBehavior May 26, 2021

BSI 

Black Screen Idiot- somebody who goes onto a video-chat site and doesnt turn there camera on or they block it from seeing them...... why go on to a video chat site if you arent going to let people see you!!!!

Friend: Yo what are you doing
You: im on chatroulette..... HOLY SHIT another black screen!!!!! im so sick of these BSI's

Friend- yeah i know, im so sick of them

BSI by # your mom July 21, 2011

BSI 

= bullshit investigation, for those who support the FTP movement and believe that every investigation is total bs, because it ruins the person's privacy

Guy: "FUCK YOU, POLICE!"
*policeman is dead silent*
(after investigation and sanctions)
Guy: "Man... that was a BSI, not a CSI!"

BSI by MindsEyeTHPS April 12, 2017

Competitive BSing 

A term Riot Games came up with to combat toxicity. Nobody actually knows what it means.

Friend (Loading into League of Legends game): What does Competitive BSing mean?
Me: Idk man I'll google it.
Me (Shortly after): Nobody knows.

Competitive BSing by zMuZZle February 5, 2020

bsian 

An asian who fails at being asian. e.g. An asian who gets Bs in school.

Asian guy: my parents are going to kill me, I got a B
Other guy: don't worry, just tell them you're bsian, not asian

bsian by mggwdr August 6, 2011