The word densimeter 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: 15
Highest Scoring Words With Friends™ Play In The Letters
Seven Letter Word Alert: (48 words)
dements, demerit, demesne, deniers, destine, diester, dieters, dimeter, eeriest, emender, emersed, enemies, entered, entrees, entries, meeters, menders, merited, metered, metrise, minders, mindset, minters, mitered, needers, needier, redeems, reedits, reemits, reested, remeets, remends, reminds, remined, remines, remints, retimed, retimes, seedier, sneered, steered, sterned, teemers, teenier, tenders, tinders, tridems, trienes