Being "Hit like Tyson" means that the girl doesn't sleep around a lot. She has only been "hit" by a few different guys.

The fighters that fought Tyson typically only took one or two punches before being knocked out. There were only "hit" a few times. A girl that has been "hit like Tyson" should be safe and not carrying any STDs.
Brad: Damn, that girl over there is a dime.
Homewood: Hell yeah, and she has been hit like Tyson so you know you won't be at the free clinic on Monday wondering what is dripping from your cock.
by ERP October 25, 2007
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