The word viceroyalty 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: 23
Highest Scoring Words With Friends™ Play In The Letters
Seven Letter Word Alert: (35 words)
acolyte, activer, aloetic, article, calorie, caviler, clarity, clavier, clayier, coalier, coalite, cotylae, cotylar, erotica, evictor, icetray, irately, layover, olivary, ovately, overact, overlay, overlit, overtly, reality, recital, royalty, tearily, treacly, variety, velaric, viceroy, victory, violate, voltaic