The word kernicterus 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
Seven Letter Word Alert: (68 words)
censure, centers, centres, cistern, cretins, cruiser, current, curries, encrust, ensuite, ensurer, enteric, enticer, entices, entries, incrust, inerter, insurer, kernite, necktie, neuters, nutsier, reciter, recites, recruit, recures, recurse, reincur, reinter, reknits, renters, rerents, rerinse, rescuer, restick, restuck, retires, retrick, retries, retunes, returns, reunite, rickets, runtier, rustier, scenter, securer, sincere, snicker, sterner, sticker, stinker, striker, suckier, tenures, tickers, tinkers, tricker, trienes, trucker, tuckers, turners, unerect, uniters, unreset, unstick, ureters, uterine