The word leptorhine 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: 17
Highest Scoring Words With Friends™ Play In The Letters leptorhine
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Seven Letter Word Alert: (28 words)
heroine, hoplite, hotline, inepter, neither, penlite, perlite, petiole, philter, philtre, phonier, pinhole, pioneer, pointer, politer, potheen, prenote, proline, protein, repilot, repoint, reptile, retinol, terpine, therein, thereon, topline, tripole