The word gravimeters 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: 20
Highest Scoring Words With Friends™ Play In The Letters
Seven Letter Word Alert: (81 words)
aeriest, aigrets, armrest, arrives, artsier, averser, averter, emirate, gaiters, gametes, gamiest, garrets, garters, gearset, germier, graters, gravest, gravies, greaser, greater, griever, grieves, grister, imagers, marries, meagrer, meatier, mergers, metrise, migrate, mirages, misaver, misgave, miterer, ragtime, reamers, rearise, reavers, reemits, regears, regimes, regives, regrate, regrets, reimage, remates, remiges, restage, restive, reteams, retears, retimer, retimes, retires, retries, retrims, reverts, reviser, riveter, seamier, seriate, seriema, serrate, sievert, sigmate, smarter, smartie, smearer, stagier, starver, steamer, striver, tarries, tearers, tearier, triages, trigram, trimers, trireme, veritas, vestige