A sex position in where the female goes down "on all fours", on her hands and knees- or feet if she wishes to stand. The male, from behind, will penetrate the female either anal or vaginally. The male will usually dominate in this position and he will get a good bit of eye candy while he's hitting it from behind, not to mention hair pulling and stuff. The female can spread out her legs or keep them together to allow for a tighter or looser feel.
We went at it doggy style in the stairwell of her apartment building. As I was about to explode I pulled out and nutted all over the floor. Hope no one slips on that.