Yahweezy, or "Yahweezy BBY!" is a term used to describe a teenage child who wants to fit in with a crowd of older kids, but simply looks pathetic. The "Yahweezy's" often have completely stupid inside jokes and wear all-girls-school shorts that increase the likelihood of people viewing that as entirely homosexual. Their mix of a ghetto "in yo face attitude" and the hardcore elements make their persona very lame. Lame is the perfect definition for this word.
"Did you see that gay kid in the Dominican shorts?"