WordNet (r) 3.0 (2006):

clean out
    v 1: empty completely; "We cleaned out all the drawers" [syn:
         clean out, clear out]
    2: force out; "The new boss cleaned out the lazy workers"
    3: deprive completely of money or goods; "The robbers cleaned us
       out in a couple of hours"

Moby Thesaurus II by Grady Ward, 1.0:

49 Moby Thesaurus words for "clean out":
   bleach, blow, blow out, bowdlerize, clean, clean up, cleanse,
   clear, clear away, clear off, clear out, clear the decks, defecate,
   delouse, deplete, depurate, deterge, drain, dry-clean, dust,
   dust off, eliminate, empty, empty out, evacuate, exhaust,
   expurgate, freshen, lustrate, purge, purify, reform, remove,
   scavenge, scour out, spruce, steam-clean, sweep out, sweeten, tidy,
   unclog, unfoul, vent, void, whiten, wipe, wipe off, wipe out,
   wipe up