What is Cow Girl?
1.
A female that likes to literally ride up and down a man's penis, or something resembling the male genitalia.
Briana Banks, loves riding the cock, she's a true cow girl.
2.
Sex position in which the guy lays on his back while the chick faces him as she sits on his dick and rides him like a stallion 
P-Phat loves the Cow Girl!
See 
Random Words:
1. 
Mary is a veggie lump
"Mean ole veggie lump"
See veggie, lump, beef, mary, mean..