Probably came from an inexperienced photographer asking what to say.
Photographer: "What am I supposed to say?"
Person in picture: "Say cheese" (as in a cheesy joke)
Photographer: "Say 'cheese'!"
by Prometh September 14, 2006
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Phrase uttered before taking a picture so it looks like everyone is smiling even though someone would rather either frown, snarl, sneer, or make an otherworldy strange or unpleasant face.

A conspiracy to get unhappy or enraged people to smile in pictures.

A conspiracy to get more people to eat cheese and wine after taking pictures.
Photographer: Say cheese!
Lauren, Dave, Jessica, and Ben: Cheese! *smile*
Barry: Fuck you! *snarl* *flicks off camera*
*click**flash*
Photographer: Smile for us, Barry. We're not stopping until you smile for us!

Three odd hours later:
Photographer: Say cheese!
Lauren, Dave, Jessica, and Ben: Cheese! *smile*
Barry: Fuck you! *frown* *flicks off camera*
*click**flash*
Photographer: Smile for us, Barry. We're not stopping until you smile for us!

Brian: Say cheese!
Cristy, Ben, Mike: Cheese!
Ben: That's strange; I have a strange craving to scarf down some Gorgonzola with some Bordeaux!
Mike: Same here! I'm gonna gorge myself on Wensleydale 'n Chardonnay!
Cristy: Let's buy all the cheese and wine we can, guys!
by someone took my name =| April 19, 2006
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Literally, a cheeseburger. Not Bob's most inspired Burger of the Day.
"Hey Bob, what's the burger of the day?" "It's the Say Cheese Burger, you should try it!"
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Say cheese and die again is the worst fucking episode of goosebumps and one of my the worst goosebumps books basically this kid becomes a fat shit do to a Polaroid camera and it’s A sequel to good episode of goosebumps called say cheese and die oh yeah there’s also a third say cheese and die book and it’s called say cheese and die screaming and it’s decent
I fucking hate say cheese and die again while I like say cheese and die
by Huntedcamerayt April 22, 2022
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Say cheese and die again is the worst fucking episode of goosebumps and one of the worst goosebumps books witch obviously the episode was based on. basically this kid becomes a fucking fatass because of a polaroid camera. And this episode is a sequel to say cheese and die witch unlike this episode is actually fucking and there’s actually a third say cheese and die book but it wasn’t turned into an episode because the goosebumps 90s show was cancelled sadly.
My dad left me at the orphanage be because they said I like to say cheese and die again. I was only joking
by Huntedcamerayt April 22, 2022
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When someone thinks they’re a wise guy and always talkin down
See ya think ya say cheese, boy. I’ll wire ya up, keep talkin

sweet!
by March 1, 2021
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