The word milemarkers 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
Seven Letter Word Alert: (33 words)
armlike, earlier, immerse, leakers, leakier, mailers, maimers, markers, marries, mealier, milkers, mismake, mismark, rammers, rammier, reakers, realers, realise, realism, reamers, rearise, reliers, remails, remaker, remakes, remarks, seamier, seriema, skimmer, slammer, slimmer, smearer, smirker