Well, we must first find out what a dist is. A dist is something of a females body part, like the clitoris, or clit. This word, however, can be used to describe a males body part, like their dick. Now on to a dist finder. When a man (or woman) looks for the parters dist. Also used as an insult, aimed toward a person, mostly someone "most likely to suck eggs" in highschool.
Girl: Dude, you are such a dist finder.
Guy: not my problem, yours for having such a small dist.
Example 2:
Man 1: Dude, that man is such a dist finder. He will never get laid.
Man 2: Yeah. Hehe.