1. The name given to an apartment which you rent weekly or monthly.
2. The name given to someone who is not cool and is dull and boring
3. The name given to a woman with no or hardly any breasts.
4. Something which is level, does not decrease or increase.
5. The name given to something filled with air which is now de-flated.
1. Wanna come back to my flat?
2. Stop being so flat, come to the party!
3. I realised last nite that my girlfriend was flat and she had been putting tissue in her bra, damn!
4. This years profit margin was flat.
5. Shit! How am i going to get to the prom now, the god damned tyres are flat.
by UncleBeef March 23, 2003
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adj. Used to describe a person of the female sex as to having no breasts.
She is flat as a board!
or
She is flat as a brick.
or
Your mom is like a carpet, flat and always getting laid by Mexicans.
by Tim Finney March 23, 2003
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an adjective used to describe a girl with no ass or tits.
by pascal July 23, 2004
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Short on cash, running low on money, going broke.
"Loan me some money!"
"Sorry, but I'm flat tonight."
by Soma9 July 15, 2008
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Used to describe soda that has been left out too long or is old, thus losing its carbon-doxide infused goodness that we like to call fizz. It is not good. It makes people sad.

flat's best friend and synonym is warm.
You asshole! This whole 12-pack is flat!
by Dre March 4, 2005
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Small-breasted.
"She has a flat rack."
by x February 1, 2003
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