[1] : The Collaborative International Dictionary of English v.0.48

weed out \weed out\, v. t.
   to selectively remove; same as weed2, v. t.; -- of things
   that are useless or harmful.
   pjc
see also:
weed2 

[2] : WordNet (r) 2.0

weed out
     v : remove unwanted elements; "the company weeded out the
         incompetent people"; "the new law weeds out the old
         inequities" syn: comb out
see also:
comb out 

[3] : Moby Thesaurus II by Grady Ward, 1.0

91 moby thesaurus words for "weed out":
   abstract, avulse, backset, cast off, cast out, chuck, clear,
   clear away, clear out, clear the decks, cultivate, culture, cut,
   cut out, delve, deport, deracinate, dig, dig out, dig up,
   disentangle, dispose of, draw, draw out, dredge, dredge up, dress,
   eject, elide, eliminate, eradicate, evolve, evulse, excavate,
   excise, exile, expatriate, expel, exsect, extract, extricate,
   fallow, fertilize, force, get out, get quit of, get rid of,
   get shut of, gouge out, grub up, harrow, hoe, liquidate, list,
   mine, mulch, outlaw, pick out, plow, pluck out, pluck up, prune,
   pull, pull out, pull up, purge, quarry, rake, rake out, remove,
   rip out, root out, root up, spade, strike off, strike out,
   take out, tear out, thin, thin out, throw over, throw overboard,
   till, till the soil, unearth, unravel, uproot, weed, withdraw,
   work, wrest out

Bale Out >> B Words
Bale Out, definition of term: Bale Out
bale+out_pag1.html

Bawl Out >> B Words
Bawl Out, definition of term: Bawl Out
bawl+out_pag1.html

Bear Out >> B Words
Bear Out, definition of term: Bear Out
bear+out_pag1.html

Bail Out >> B Words
Bail Out, definition of term: Bail Out
bail+out_pag1.html

Back Out >> B Words
Back Out, definition of term: Back Out
back+out_pag1.html

Air Out >> A Words
Air Out, definition of term: Air Out
air+out_pag1.html

Ask Out >> A Words
Ask Out, definition of term: Ask Out
ask+out_pag1.html

Act Out >> A Words
Act Out, definition of term: Act Out
act+out_pag1.html