To be exceptionally smug, full of oneself.
after that gummer i had a shit eating grin
by butthead April 29, 2006
Get the shit eating mug.
Also refered to as an eater of Dung - the uncontrolable urge to snack on dung or feces by Amberang or close associate.
No Know examples as Amberang is a very seceretive shit eating person and hides her habit well
by Rexy Loo May 26, 2006
Get the shit eating mug.
when one proceeds to eat ones own shit.
hey man you shit-eating today?
by crazy eyes0327! February 23, 2012
Get the shit-eating mug.
When someone is talking shit and they continue to run their mouth, and you beat the shit out of them and make them eat shit.
Guy 1: "Man's you're such a pussy"
Guy 2: Beats the shit out of guy 1 then makes guy 1 eat shit. Then Guy 2 says "Talk Shit, Eat Shit.
by crosk December 5, 2011
Get the Talk Shit, Eat Shit mug.
Sometimes shit-eating grin.

(1) n. A shit eating grin is a very wide and, to the outside observer, stupid looking grin, usually showing smugness, self-satisfaction, or inner humor. The term is most often seen in the expression "Wipe that shit eating grin off your face!", usually said by the aforementioned outside observer. This observer-based definition makes "shit eating grin" the negative counterpart to "You look like the cat who ate the canary." While the two expressions describe the same grin, they have very different connotations. This definition has nothing to do with the term "shit eater".

(2) n. Someone donning a forced smile in an uncomfortable, embarassing, or compromising situation could be said to have a shit eating grin. Because an uncomfortable situation is much more closely related to "eating shit" than smugness, it is plausible to assume that this is the first definition, although far from the most common, and that the above definition is a result of drift from this one.

Both of these uses are documented in the Oxford English Dictionary no earlier than 1957.
(1) Upon telling Elaine he knew a secret, Jerry donned a shit eating grin and refused to reveal it.

(2) Forced to admit defeat, the politician managed a shit eating grin as he called for and end to "bipartisan rhetoric".
by GuildNavigator84 February 8, 2006
Get the shit eating grin mug.
"You got the promotion! I knew there was a reason for that shit-eating grin."
by AbnormalBoy September 3, 2004
Get the shit-eating grin mug.
The smirk on one's face that makes you want to punch it.
Larry thinks he's funny with his shit eating grin.
by capnbarfy May 28, 2011
Get the shit eating grin mug.