Wordnet 3.0
NOUN (1)
1. 
 a variable load on a structure (e.g. a bridge) such as moving traffic; 
[syn: live load, superload]
WordNet (r) 3.0 (2006):
superload
    n 1: a variable load on a structure (e.g. a bridge) such as
         moving traffic [syn: live load, superload]