The word unassertive 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: (92 words)
aeriest, antsier, arenite, aunties, austere, avenues, earnest, easiest, eastern, ensears, ensuite, ensures, entries, enviers, euaster, inserts, instars, insures, inverse, inverts, invests, naivest, nastier, natives, natures, nearest, nesters, neuters, nutsier, ravines, reissue, renests, resaves, reseats, resents, restain, restive, retains, retinas, retunes, reunite, revises, revuist, sateens, satires, saunter, seaters, seitans, seitens, senates, sensate, seriate, servant, sestina, sestine, sievert, sinters, sinuate, stainer, starves, sterane, stivers, strains, striven, strives, suavest, suiters, sunrise, sunstar, sustain, taverns, teasers, tenures, trainee, triaene, trienes, uniters, unreset, unrests, unrivet, unseats, ureases, urinate, uterine, vainest, venture, verists, veritas, versine, veteran, virtues, viruses