The word centroids 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: 14
Highest Scoring Words With Friends™ Play In The Letters
Seven Letter Word Alert: (35 words)
ceroids, cinders, cistern, citrons, coedits, coiners, cornets, credits, cretins, cronies, directs, discern, editors, erotics, indorse, nordics, norites, noticed, notices, orients, recoins, rescind, rodents, roisted, rosined, scorned, section, snorted, sortied, steroid, stonier, storied, tierods, tinders, triones