The definition of feckless is someone who is ineffective or irresponsible.(adjective)
A person who cannot be trusted to take on responsibility is an example of someone who would be described as feckless.
See feckless in Webster's New World College Dictionary
Origin: Scot < feck (aphetic for effect) + -less
See feckless in American Heritage Dictionary 4
Origin: Scots feck, effect (alteration of effect)
Origin: + -less.
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