WordNet (r) 3.0 (2006):

chewy
    adj 1: requiring much chewing
    2: (of a consistency) requiring chewing; "chewy caramels"

Moby Thesaurus II by Grady Ward, 1.0:

25 Moby Thesaurus words for "chewy":
   cartilaginous, cohesive, coriaceous, durable, fibrous, gristly,
   hard, hardy, lasting, leatherlike, leathery, resistant, ropy,
   sinewy, stiff, stringy, strong, stubborn, tenacious, tough,
   tough as leather, untiring, vigorous, viscid, wiry