The word preconceiving 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: 30
Highest Scoring Words With Friends™ Plays In The Letters preconceiving
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Seven Letter Word Alert: (33 words)
coining, concern, connive, convene, coreign, cornice, corning, crevice, eccrine, environ, evening, generic, invoice, ironing, nerving, nonepic, opening, opining, peering, peeving, piecing, pioneer, porcine, pricing, proving, reeving, reicing, reining, revoice, veering, veinier, veining, voicing