The word dripstone 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: (44 words)
deports, deposit, diopter, dioptre, dopiest, editors, indorse, norites, orients, peridot, periods, pointed, pointer, ponders, portend, posited, postern, printed, pronest, protein, pterins, repoint, respond, rodents, roisted, ropiest, rosined, snorted, sortied, spinode, spirted, sported, steroid, stipend, stonier, storied, striped, tierods, tinders, topside, torpids, triones, tripeds, tripods