The word seasonableness 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 seasonableness
:
Seven Letter Word Alert: (21 words)
abalone, anneals, baleens, blesses, enables, ennoble, enolase, enseals, lassoes, lessees, lessens, lessons, nabales, nanobes, nonsale, noseans, oneness, seabass, seasons, seeable, sonless