The word leatherettes 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: (44 words)
athlete, attelet, elaters, halters, hatters, healers, heaters, lathers, leather, letters, rattles, realest, reheats, reheels, relates, release, restate, retaste, seether, settler, shatter, sheeter, shelter, slather, starlet, startle, stealer, stealth, tartest, tartlet, tatters, tattler, tattles, teeters, teether, teethes, testate, tethers, theater, theatre, thereat, threats, treelet, trestle