The word dichromats 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 dichromats
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Seven Letter Word Alert: (23 words)
astroid, atomics, carotid, chamois, chariot, coadmit, diatoms, dirhams, domatic, drachms, drastic, hairdos, haricot, mastoid, midrash, moschid, orchids, ostrich, rhotics, somatic, stardom, stomach, toadish