To indicate a sad time, or some kind of disappointment.
"Hey man, you going out to the bars with us tonight?"

"Nah, girlfriend is dragging me to a chick flick. It's so flat soda."

or

"Working late again?"

"Yeah, it's like flat soda."
by jsmith0708 April 7, 2008
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A girl with an attractive body, but an ugly face. She is usually used and abused for sexual pleasure by men, but never wifed. You just beat her pussy up and bounce.
Dude 1: Yo! Did you hit up that girl from last night?

Dude 2: Nah. Shes like flat soda. Ima just keep her around in case I get thirsty!
by The Bizzle 1978 March 17, 2014
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Got some flat diet soda? If it contains phosphoric acid and/or citric acid, don't throw it away, put it in a spray bottle and use it as a cleaner. Do NOT use regular (sugary) soda, or you'll make a super sticky mess!
Flat diet soda cleans well, and is safe for babies and pets.
by Shelly Bozdog December 9, 2006
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