The word agglutinins 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: 19
Highest Scoring Words With Friends™ Plays In The Letters agglutinins
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Seven Letter Word Alert: (34 words)
aisling, angling, anglist, gaining, gaiting, gusting, insulin, intagli, inulins, lasting, lignins, linings, listing, lunging, lusting, nailing, sailing, salting, signing, silting, singing, slating, staging, suiting, tailgun, tailing, tilings, tinging, tunings, unaging, unalign, uniting, unsling, unstain