The word disestablish 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: 19
Highest Scoring Words With Friends™ Play In The Letters
Seven Letter Word Alert: (48 words)
abseils, aidless, albites, alibies, ashiest, ashless, astilbe, baldest, baldish, bassets, bassist, bedsits, biassed, biasses, blasted, blissed, blisses, dailies, daisies, delists, desalts, desilts, desists, details, dilates, disable, distils, halides, halites, hassles, hatless, hissies, lassies, liaised, liaises, libated, libates, sadists, shields, sidelit, siestas, slashed, slashes, stabled, stables, stashed, stashes, tassels