"to hide, conceal," early 14c., a Northern English and Northern Midlands word, from Old Norse fela "to hide," from Proto-Germanic *felhan (source also of Gothic filhan "to hide, bury," Old English feolan "enter, penetrate, pass into").
feal (adj.)
"faithful," 1560s, not found in Middle English but apparently from Old French feal "faithful, loyal, true, sincere," collateral form of feeil, from Latin fidelis "loyal" (see fidelity).
fay
faze
FBI
FCC
FDA
feal
fealty
fear
fearful
fearless
fearsome