Search Result for "sone": 
Wordnet 3.0

NOUN (1)

1. a unit of perceived loudness equal to the loudness of a 1000-hertz tone at 40 dB above threshold; 



WordNet (r) 3.0 (2006):

sone
    n 1: a unit of perceived loudness equal to the loudness of a
         1000-hertz tone at 40 dB above threshold