The word percussing 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: 20
Highest Scoring Words With Friends™ Play In The Letters percussing
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Seven Letter Word Alert: (30 words)
cringes, crispen, cruises, cursing, cusping, cussing, ingress, insures, percuss, pincers, pingers, princes, prussic, purines, pursing, pussier, resigns, respins, reusing, signers, singers, snipers, spicers, springs, spruces, spurges, sunrise, suspire, uprisen, uprises