The word eiderdowns 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 eiderdowns
:
Seven Letter Word Alert: (37 words)
deniers, denoise, derides, desired, dewired, dewires, dowdier, dowered, downers, downier, dowries, dresden, drowned, drowsed, endorse, endowed, indorse, newsier, nodders, reddens, reendow, resided, resowed, rewinds, rosined, rowdies, sinewed, snowier, soddier, sworded, weiners, weirdos, widened, widener, wieners, winders, wonders