Corkass can be taken literally or as a figure of speech, an idiom. The literal term is someone who has a cork up their ass. If they have a cork up their ass, they need medical help to dislodge the cork in their ass, or butt. A non-literal term would be someone who is cranky or rude, acting as they would if they did indeed have a cork up their ass.
Doctor Jim, we have another corkass in our lobby.
Mark wouldn't let me come over today because of my weight. What a corkass.
by I'mVeryStupid November 20, 2017
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One who has a cork up their ass, either literally or figuratively. A literal corkass should seek medical attention to remove the cork from their ass. A figurative corkass constantly acts uptight and agitated, as if they do, in fact, have a cork lodged in their asshole.
"Doctor, there's another corkass in the surgery ward that requires attention."

"I asked my friend for a lift to work today, but he said no on account of it being out of the way. What a corkass."
by Corkasser October 22, 2008
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One whose ass is so full of blackheads, acne, hair that was shaved about 2 days ago so that it's just now growing back, or any sick combination of the 3, that it has the appearence of cork.
kid 1: "Okay, I officially saw the grossest thing in the locker room today."

kid 2: "wtf do i want to know?"

kid 1: "probably not but i'm gonna tell you anyway. that kid etherage is officially a corkass."

kid 2: *pueks*
by overlordofdiction777 December 8, 2008
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