dollar dick

When wrapping a dollar around a penis to measure girth, a dollar dick is so thick that the ends of the dollar do not touch.

Allison: "Yo, do you know Victor?"
Erin: "Yeah, the guy you got with last night?"
Allison: "You know he has a dollar dick?"
Erin: "Must have been girthy"
Allison: "Yup, it was great. Less painful than I thought"