The word jitteriness 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: 21
Highest Scoring Words With Friends™ Play In The Letters jitteriness
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Seven Letter Word Alert: (30 words)
entries, inserts, jesters, jetties, jitters, nesters, netters, nitrite, nittier, renests, resents, retests, retints, seitens, sestine, setters, sinters, sitters, streets, tensest, tenters, tentier, tersest, testers, testier, tiniest, tinters, tintier, trienes, trijets