DuckCorp Dico

Found one definition

1.                 From WordNet (r) 3.0 (2006):
                   
   
   
                   
                     
   ALS
       n 1: thickening of tissue in the motor tracts of the lateral
            columns and anterior horns of the spinal cord; results in
            progressive muscle atrophy that starts in the limbs [syn:
            amyotrophic lateral sclerosis, ALS, Lou Gehrig's
    disease]