The word blunderbuss 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: 22
Highest Scoring Words With Friends™ Play In The Letters blunderbuss
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Seven Letter Word Alert: (23 words)
blunder, blurbed, budless, bundles, burbled, burbles, burdens, dubbers, nubbled, nubbles, resnubs, rubbles, snubbed, snubber, subduer, subdues, subrule, suburbs, sunbeds, unbless, unblurs, undress, unruled