The word haemoglobins 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: 24
Highest Scoring Words With Friends™ Play In The Letters
Seven Letter Word Alert: (79 words)
abolish, agonies, agonise, agonism, albinos, ambling, animose, bangles, bashing, beaming, begloom, begonia, belongs, bemoans, blaming, blemish, bologna, boogies, boolean, booming, eloigns, english, enigmas, gambles, gambols, gasohol, geminal, genials, gliomas, gmelina, gnomish, goalies, goblins, haemins, halogen, healing, hoagies, hobnail, homages, ignoble, imagoes, inhales, lagoons, lambing, lashing, leasing, legions, lesbian, lingoes, longish, looming, loonies, loosing, maligns, mangles, mangoes, manhole, mashing, meshing, mingles, mobiles, mongols, moolahs, noisome, nosebag, obliges, oblongs, oleosin, sealing, sealion, seaming, semilog, seminal, shamble, shaming, shingle, shoeing, shooing, soloing