The Collaborative International Dictionary of English v.0.48:
Nonextensile \Non`ex*ten"sile\, a. Not extensile; incapable of being stretched. [1913 Webster]WordNet (r) 3.0 (2006):
nonextensile adj 1: not extensile [syn: nonextensile, inextensible, nonprotractile] [ant: extensible, extensile]