Wordnet 3.0
NOUN (1)
1. 
 a unit of weight equal to one sixteenth of a pound or 16 drams or 28.349 grams; 
[syn: ounce, oz.]
WordNet (r) 3.0 (2006):
oz.
    n 1: a unit of weight equal to one sixteenth of a pound or 16
         drams or 28.349 grams [syn: ounce, oz.]