1. Encouraging directive made by a male for a female (or male, if that's how you swing) partner to directly engage the head of the penis in either oral, vaginal or some other orifice-centered sexual act.

2. A derogatory exclamation made from one male to another as an insult, much akin to telling someone to "suck my dick".

When you eat dirt for the first time and leave your family to build a shack in the woods