1 definition by JasonBourneHimself

Acronym for tits by fat. Used when a fat girl (or her almost always equally fat boyfriend) attempts to brag about their large breasts. In reality they are extremely saggy and often accompanied by a disgusting set of stretched and contorted nipples.
Tom: Dude, Cynthia is the best girlfriend ever. Her tits are massive!

James: For Christ sake Tom, she weighs 350 pounds. That damn pig has a severe case of TBF.
by JasonBourneHimself April 30, 2010
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