The word chivalrously 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: 26
Highest Scoring Words With Friends™ Play In The Letters
Seven Letter Word Alert: (29 words)
arillus, callous, charily, chloral, chorals, chylous, clayish, collars, curials, horsily, ischury, lousily, lyrical, oculars, olivary, oscular, rosalic, saucily, saviour, savoury, scarily, scholar, schorly, shrilly, slouchy, surlily, various, virally, vocally