The definition of implacable is someone or something who cannot be calmed or made less angry.(adjective)
An example of implacable is a screaming child who won't listen to reason.
See implacable in Webster's New World College Dictionary
Origin: Fr < L implacabilis
See implacable in American Heritage Dictionary 4
Origin: Middle English
Origin: , from Old French
Origin: , from Latin implācābilis
Origin: : in-, not; see in-1
Origin: + plācābilis, placable; see placable.
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