A sarcastic remark to an unamusing statment, comment, joke, or question. Most people when saying "Yo Sick" tend to point both arms in the direction of the person who has made the idiotic comment. It is also custom to add the person's name at the end of the "Yo Sick"
Yo Sick: Adjective describing someone unamusing

Person 1: Stupid comment nobody cares about
Person 2: Yooo sick

Eckel: Guys the broncons are going to win the superbowl and the Uconn huskies are going to win the NCAA national championship
Everyone in the General Area: Yoooo Sick Eckel

Austin Allen: Whats up Davey Burgers
Eckel: Yooo sick Don
by Dan Archer July 11, 2008
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A phrase popularized by a bunch of brain-dead 8th graders in a LasVegas middle school. It's usually said prior to an un-funny joke.
Irvin: I just found $5!
Yumi: That's pretty super sick yo!
by EmersonH September 20, 2009
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