Mammoth Uncensored Word List:
50 words that are 16 letters long beginning with f in the mammoth uncensored word list.

factitiousnesses faintheartedness fallaciousnesses falseheartedness falsifiabilities familiarizations fantasticalities farfetchednesses farsightednesses fascioperiosteal fashionabilities fastidiousnesses fathomlessnesses featherstitching feeblemindedness felicitousnesses femtochemistries ferroelectricity fibromyxosarcoma fictionalisation fictionalization fictitiousnesses figurativenesses fissionabilities flabbergastingly flagitiousnesses flexographically flibbertigibbets flibbertigibbety flightworthiness fluoroquinolones fluoroscopically fluviolacustrine forebodingnesses forehandednesses foreseeabilities forethoughtfully formidablenesses formularizations forthrightnesses fortuitousnesses frankheartedness fraudulentnesses freehandednesses frenchifications friendlessnesses frontosphenoidal fundamentalistic futilitarianisms futurelessnesses