The word shorteners 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: 13
Highest Scoring Words With Friends™ Play In The Letters shorteners
:
Seven Letter Word Alert: (30 words)
estrone, heteros, hornets, hotness, nesters, norther, rehones, renests, renters, rerents, resents, reshoes, reshore, resorts, resters, restore, rhetors, rosters, shorten, shorter, snorers, snorter, sorters, stenose, stereos, sterner, stoners, tensors, thereon, thrones