The word deerstalker 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: 17
Highest Scoring Words With Friends™ Play In The Letters
Seven Letter Word Alert: (64 words)
alerted, alerter, altered, darkest, darters, dealers, dearest, deerlet, delates, deleter, deletes, elaters, kestrel, larders, leaders, leakers, readers, reakers, realers, realest, realter, reasked, reasted, redates, redeals, redealt, reekers, reelers, reested, related, relater, relates, release, rereads, restake, retaker, retakes, retards, retears, retrade, retread, retreed, retrees, sedater, serrate, skelder, skelter, sleeker, sleeted, stalked, stalker, starker, starred, stealer, steeled, steered, steerer, talkees, talkers, tasered, tearers, traders, treader, treadle