A person, usually a dude, who has never had anyone tell them that they aren't funny. They continually spit out little jokes in any converstion, regardless of who they may be interrupting, as long as they get a few laughs. What happens when they don't get laughs? They're up and running in a matter of seconds to try to make up for it... To fix a sphinctor boy, just wait until he has one of those "rare" jokes where nobody chuckles, then call him out and embarrass him in front of whoever is around. This can fetch varied results, but usually shuts the person up for 3 to 5 days. Sphinctor boys are becoming more and more abundant, and it's becoming harder to pick them out by how they look. Be sure that you give potential sphinctor boys three strikes, because lets face it, everyone gets excited sometimes. After that, though, they are fair game for a good old fashioned shut the fuck up.
Teacher/Professor: Ok class, today kicks off the first day of our American history chapter. (Sphinctor boy, we'll say Chad..) Chad, take that hat off please.

Chad (Sphinctor boy): Hey guys, look! It's me, Uncle Sam! And I WANT YOU!!! Hahaha, get it? I WANT YOU!!!...it's what Uncle Sam says!! Good times...good times....

Girl who feels awkward so she giggles: hehehe
by Chad??? September 8, 2007
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