Someone who steps into the realm of complete assholeness without realizing it. Someone who crosses the line; takes it too far.
In a sentence: "Dude you just pulled a yost!"

In an example: Phillip jokingly flicked a bit of water at Joe from his cup. In return, Joe poured his entire cup of water on Phil, thinking it was completly in context.
by Mr. B[Pwnsnoobz] January 24, 2007
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Ignorant, no car-having, no job-having, ADD, minimal pubic hair, half Frankenstein/half pitbull/half-eaten cheeseburger
Yost, get that man's peepee ot of your mouth
by Happy November 16, 2003
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1. To talk about spending money frivilously. 2. To complain about; bitching. 3. To avoid one's duties at work or at home.
1. Ed was yosting again today; he was talking about buying a new car with a trailer hitch to move that new boat he's going to buy.
2. Stay away from Carl today, he's yosting about his wife again.
3. I'm not doing any work today; I'm just yosting.
by Mike Lowry May 23, 2007
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v. to go on vacation and peace out from your job without any notice. deciding to quit while on vacay. not giving a fuck about your job (or reputation).
"Oh shit. Did you hear Jeff went to Hawaii and fucking yosted? WTF?"
by wo0t_oot July 20, 2016
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Literally just the past tense of yeast...
What fucking sentence do you put "yost" in??
by DUCKt Tape June 2, 2018
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Player of Sports; most specifically Basketball or Chess. Usually used as a minor insult.
That yost is toast!
by David January 5, 2004
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