The Collaborative International Dictionary of English v.0.48:
Weed out \Weed out\, v. t. to selectively remove; same as weed[2], v. t.; -- of things that are useless or harmful. [PJC]WordNet (r) 3.0 (2006):
weed out v 1: remove unwanted elements; "The company weeded out the incompetent people"; "The new law weeds out the old inequities" [syn: weed out, comb out]