1. Venusian Artist
2. One who can and does successfully meet women and collect phone numbers, go on dates, and eventually has intercourse with his desired females.
3. One who uses psychology and/or sociology in order to get what he wants from the opposite or same sex (depending on his or her sexual preference), and has a large success rate.
4. One who studies and practices the art of Pickup, which includes several different areas of study (including social dynamics, psychology, sociology, body language, etc).
5. Term made extremely popular by Mystery and his show on VH1, which taught "losers" how to talk to women and build their self confidence, and transforming them into "pickup artists". Also made popular beacuse of the book "The Game" written by Neil Strauss which explains his transformation from a "nerdy" writer for Rolling Stone Magazine into an internationally known pickup artist.
If you know how to enter a random group of people and leave with the woman you were going after within that group, you can quite possibly be a pickup artist.