The word rationalistic 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: 18
Highest Scoring Words With Friends™ Play In The Letters
Seven Letter Word Alert: (57 words)
actants, actions, alicant, altoist, arctans, artisan, atonias, atonics, attains, cantors, carinal, cartons, cations, cattail, citator, citrons, clarion, coaltar, coastal, colitis, cranial, cratons, iconist, incisor, initial, intorts, italics, lacinia, lariats, liaison, nicosia, nostril, octants, oilcans, rations, rattail, rattons, ricotta, rosalic, saltcat, satanic, satiric, scrotal, silicon, sirloin, solicit, starlit, station, stoical, straint, tailors, tantric, tartans, titanic, transit, tricots, tsarina