The word gastrulation 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™ Plays In The Letters
Seven Letter Word Alert: (86 words)
against, agnosia, agonist, agoutis, airguns, altoist, analogs, anglist, angular, arousal, artisan, atonias, attains, austral, gastrin, glottis, glutton, granola, guarani, guitars, iguanas, insular, intorts, intrust, languor, langurs, lariats, lasting, lousing, lunaria, lusting, natural, nitrous, nostril, orating, ousting, outgain, outgrin, outings, outlast, outrant, outsail, outsang, ragouts, rainout, ratings, rations, rattail, ratting, rattons, rituals, rotting, rousing, routing, rulings, rusting, rutting, saguaro, salting, sangria, saurian, signora, slating, soaring, sorting, souring, staring, starlit, stating, station, storing, straint, sultana, tailgun, tailors, tartans, tasting, tauting, titular, touring, tourist, touting, transit, truants, tsarina, urinals