Two of hip-hop's youngest guns unite on Mac Miller's 'Definition of Cool,' featuring Diggy Simmons.

The lyrical content had us checking Diggy's age (16) out of concern, but since Mac's only 20, we're guessing Diggy's pops, the legendary Rev Run of Run DMC, doesn't mind the two trading swag verses about bitches.

"Spittin' flames so they burn in my tongue/ Bitches wanna f---, but they heard that I'm young." Mac spits. "And they still do, I'm a stick around call me mildew/ Go and stay in Bel Air like Uncle Phil do."

Diggy strangely adopts a British lilt for his verse, ala Nicki Minaj, kicking some risque lines of his own.

"Shots at a general, roll like an inner tube/ Drinking on tigers blood, that's what winners do," the youngster rhymes. "It seems as if you'd like to hang from my genitals/ Whoa, pause, oh, gosh."

Just like Mac's other recent track 'Loud,' this was produced by Big Jerm, and is likely to appear on his upcoming mixtape 'Macadelic.' Meanwhile, Diggy's long awaited debut 'Unexpected Arrival' is due in stores March 20.

Listen to Mac Miller's 'Definition of Cool' Feat. Diggy Simmons

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