look up any word, like blumpkin:
 
2.
1) A hasty way to end a conversation.

2) Officially an abbrieviation of 'Ok, thank you, bye.'

3) Most commonly used sarcastically after an insult to try and make it sound jokey (it usually isn't...)
Guy: Hey, d'you remember that guy you pulled last night? You know! The vertically challenged asthmatic one with a glandular disorder?

Girl: Hey, d'you fancy shutting the fuck up now? kthnxbai!

Guy: ...
by CaramelLatte April 05, 2010
 
1.
Contraction of Ok, thanks, bye.
Used when you want someone to shut up (you're not exactly trying to be polite,) yet it's not considered as an insult like STFU. Also it can be used when answering a stupid n00b question, or after scolding someone.
I'm not arguing anymore. kthnxbai.
Stop that or I'll ban you. kthnxbai.
^ above isn't as insulting as STFU N00B!
by zirku September 08, 2005
 
3.
to b-slap and walk away
I'm breaking up with you, k thnx bai.
by Natali3 November 07, 2007
 
4.
something that you say when you kinda want to rush out of a chatroom or when someone won't stfu.
In science class:
"So that's your homework. Go to lunch or whatever."
" KTHNXBAI!"
by alygrl1395 January 20, 2009
 
5.
What people say when they have done something wrong on a internet conversation.
Harry: Do you pick your nose?
Frank: WHAT?
Harry: kthnxbai
by Justher May 17, 2010
 
6.
Contraction of "okay, thank you, bye".

Possibly the stupidest way of trying to end an argument ever. Used by prissy internet douchebags.
"You have no right to come around here and talk to me like that!

kthnxbai!"
by nycto May 11, 2004