1590s, from feck, "effect, value, vigor" (late 15c.), Scottish shortened form of effect (n.), + -less. Popularized by Carlyle, who left its opposite, feckful, in dialectal obscurity. Related: Fecklessly; fecklessness.
feckless attempts to repair the plumbing
febrile
February
fecal
feces
fecit
feckless
feculent
fecund
fecundity
fed
fedayeen
