The word reversibility 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: 23
Highest Scoring Words With Friends™ Play In The Letters
Seven Letter Word Alert: (47 words)
berries, bitsier, blister, brevets, brevity, bristle, bristly, evilest, eyeslit, ileitis, liberty, rebites, reliers, relives, restive, restyle, retiles, retires, retries, revelry, reverbs, reverts, reviler, reviles, reviser, revisit, ribeyes, riblets, risible, riveter, servile, servlet, sievert, siltier, silvery, sterile, stivier, striver, stylier, svelter, sylvite, tersely, trebles, veilers, veilier, visible, visibly