Search Result for "nonflammable": 
Wordnet 3.0

ADJECTIVE (1)

1. impossible to ignite; 



The Collaborative International Dictionary of English v.0.48:

nonflammable \nonflammable\ adj.
   Not easily ignited, and burning only slowly if ignited.
   [Narrower terms: noncombustible (vs. combustible),
   incombustible] WordNet 1.5]


WordNet (r) 3.0 (2006):

nonflammable
    adj 1: impossible to ignite