The word brainstems 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™ Play In The Letters
Seven Letter Word Alert: (50 words)
absents, ambient, ambries, antsier, artsmen, baiters, banters, barites, basters, batsmen, bestman, betrims, braises, breasts, inmates, inseams, inserts, instars, marines, martens, martins, masters, minaret, minters, misseat, misters, nastier, raiment, rebaits, remains, remints, restain, retains, retinas, satires, seitans, seminar, sestina, sinters, sirname, smarten, smartie, smiters, stainer, stamens, strains, streams, timbers, timbres, tsarism