DuckCorp Dico

Found one definition

1.                 From WordNet (r) 3.0 (2006):
                   
   
   
                   
                     
   whiten
       v 1: turn white; "This detergent will whiten your laundry" [syn:
            whiten, white] [ant: black, blacken, melanise,
            melanize, nigrify]