The word racecourse 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: 17
Highest Scoring Words With Friends™ Play In The Letters
Seven Letter Word Alert: (24 words)
accruer, accrues, accurse, accuser, acerose, acerous, arouser, careers, carouse, coarser, coercer, coerces, courser, creaser, erasure, rearose, recures, recurse, reoccur, rescore, rescuer, scarcer, scourer, securer