The word cartilages is playable in Words With Friends™, no blanks required. Because it is longer than 7 letters, you would have to play off an existing word or do it in several moves.
Words With Friends™ Letter Score: 16
Highest Scoring Words With Friends™ Play In The Letters
Seven Letter Word Alert: (42 words)
acaters, aerials, agarics, agatise, aiglets, aigrets, article, atresia, cagiest, cartage, cartels, castile, clarets, cristae, eartags, eclairs, elastic, gaiters, garlics, gastric, glacier, glister, gracile, gristle, laagers, laciest, lactase, largest, lariats, ligates, raciest, realist, recital, regalia, retails, saltier, scalier, scarlet, slatier, stagier, teargas, triages