The word malingerer 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: (38 words)
aligner, angrier, earlier, earring, enlarge, geminal, general, germane, germier, gleaner, gmelina, gnarler, grainer, gremlin, learing, learner, leering, lineage, mangier, mangler, manlier, mariner, marring, meagrer, mealier, melange, mileage, mineral, mingler, rangier, realign, reaming, rearing, reeling, regimen, reigner, reimage, relearn