The word coarctations 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)
actants, actions, arctans, arctics, artisan, atonias, atonics, attains, cantors, cartons, cartoon, cations, citator, citrons, coactor, coarcts, consort, contact, contort, coronas, cottons, cratons, intorts, notator, octants, oncotic, oration, raccoon, racoons, rations, rattons, rattoon, ricotta, risotto, satanic, scoriac, station, straint, tactics, tantric, tartans, tictacs, tictocs, toccata, torsion, transit, tricots, tsarina