The word worthiness 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: 16
Highest Scoring Words With Friends™ Play In The Letters
Seven Letter Word Alert: (41 words)
heroins, histone, hornets, hosiers, hotness, inserts, inshore, norites, nosiest, orients, reshown, reshows, rosiest, seniors, shiners, shorten, showers, showier, shrines, sinters, snowier, sorties, stoners, stonier, stonish, stories, swisher, tensors, thiones, thrones, triones, twiners, twonies, whiners, whitens, winters, wishers, withers, witness, worsens, writhes