The word chemosynthesis 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: 27
Highest Scoring Words With Friends™ Play In The Letters
Seven Letter Word Alert: (81 words)
cements, cenotes, cession, chemist, chimney, chymist, coesite, consist, cosiest, cosines, coyness, cystine, cytosis, emetics, encysts, enocyte, entices, ethnics, ethynes, etymons, eyeshot, hessite, histone, hitches, homiest, honesty, hostess, hotness, hymnist, incests, incomes, inocyte, insects, isohyet, isonyms, meioses, miocene, mitoses, moisten, mycoses, mycosis, myosins, myotics, mystics, nemesis, neocyte, nosiest, notches, notices, octenes, octynes, oecists, onetime, osseins, schemes, schisms, schists, scythes, section, seitens, session, sestine, shyness, siemens, sitcoms, snitchy, society, somites, stenchy, stenose, stomies, stonish, stymies, syenite, systems, techies, theisms, theonym, thiones, thymine, tocsins