The age at which a young lady(a teenager) is considered a 'viable' conquest by a grown man.
"Hey, Adam, how old is that younger sister of yours?"

"She's not f-teen yet mo-fo, so stay the fuck away from her."

"Whoa, whoa, whoa... you thought that girl with her learners permit was f-teen. Isn't your sister almost out of high school?"

"Yeah... go ahead and mac down on her..."
by Anonymous August 15, 2003
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