The word demeanours 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: 16
Highest Scoring Words With Friends™ Play In The Letters
Seven Letter Word Alert: (43 words)
amender, anomers, aroused, asunder, daemons, damners, demeans, enamors, enamour, endears, endorse, endures, ensured, eudemon, manured, manures, meander, measure, medusae, menders, moaners, moderns, mourned, neuroma, oarsmen, radomes, randoms, readmes, reamend, remands, remends, remound, renamed, renames, resound, resumed, roadmen, ruesome, smeared, sounder, surname, unarmed, undoers