The word colorlessness 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: 19
Highest Scoring Words With Friends™ Play In The Letters colorlessness
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Seven Letter Word Alert: (32 words)
censers, censors, cloners, closers, colonel, console, coolers, creoles, creosol, cresols, cresses, crosses, enclose, encores, enrolls, lessens, lessons, lessors, loosens, necrose, noosers, reclone, reclose, resells, resoles, screens, scrolls, secerns, sellers, sensors, sonless, sooners