The word calisthenics 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: 22
Highest Scoring Words With Friends™ Play In The Letters
Seven Letter Word Alert: (84 words)
accents, accites, achiest, aclinic, actinic, aitches, alethic, ascents, ascetic, ascites, ashiest, cachets, calcine, calcite, caliche, caltech, cancels, cantles, caseins, castile, castles, catches, chaises, chalets, chalice, chancel, chances, chasten, chilies, chisels, chitlin, ciliate, cinches, clashes, classic, clastic, cliches, clients, clinics, clitics, elastic, elastin, elicits, enlists, entails, ethical, ethnics, halites, hastens, hatless, ichnite, icicles, iciness, incests, incises, incites, inhales, insects, ischiac, ischial, italics, laciest, laicise, lancets, latches, liaises, lichens, listens, nailset, sachets, salient, salines, satchel, scathes, sciatic, secants, seitans, sestina, silanes, silents, silicas, stances, stencil, tinsels