Almost no choice of chicks/dudes to date in a certain group of people.
Dude, all the chicks in my class are fugly! That's slim pickins dude...
OR
Dude, there are only three girls in this room and like 17 guys. Slim pickins man....
An adjective to describe a place in which there is a large amount of useful discarded items that you can salvage. This is similar to how a chicken or group of chickens pick(s) at the ground to find insects to eat.
Hey man, check out 123 Anyplace Road! They're having a yard sale and the free stuff section is like chicken's pickins!
Clean pickins is something that you do not have to scrutinize or even think twice about how perfect it is. If it's clean pickins, it don't need no nitpickin!
My Subaru I am trading in is clean pickins, boy! You need to tell your manager there ain't no need to nit pick it!