floppy disk drive (FDD)
FLOPS (floating-point operations per second)
floptical
floptical disk
flora
florae
floral
floreal
floreated
florentine
florescence
florescent
floret
floriate
floriation
floribunda
floricolous
floricultural
floriculture
floriculturist
florid
floridity
floridness
floriferous
floriform
florigen
florigenic
florilegium
florin
floripparious