The word suppertime 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: 20
Highest Scoring Words With Friends™ Play In The Letters suppertime
:
Seven Letter Word Alert: (29 words)
empires, emptier, empties, epimers, impetus, metrise, muppets, mustier, peptise, permits, permute, preempt, premise, presume, pumpers, reemits, repipes, repumps, respite, restump, retimes, spumier, stepper, stumper, supreme, tempers, tippers, umpires, uptimes