I'm 25 and am considered by some to be rather promiscuous. How do we define "promiscuous"?

How do we define "promiscuous" or "slutty" if you will? What's the barometer for a 25 year old male living in a big city? Say we break it down by numbers...I would venture to say that under 20 partners is considered fine. 20-40 might raise a few eyebrows. Anything over 40 is a bit slutty. And anything exceeding 100 is definitely slutty. Thoughts?