Simple Definition of implacable
: opposed to someone or something in a very angry or determined way that cannot be changed
Examples of implacable in a sentence
He has an implacable hatred for his political opponents.
<an implacable judge who knew in his bones that the cover-up extended to the highest levels of government>
Did You Know?
Implacable comes from the Latin word implacabilis, with which it shares the meaning "not easily placated." Ultimately, it comes from the verb placare, meaning "to calm" or "to soothe." Implacable adds the negative im- to the root to describe something that cannot be calmed or soothed or altered. The root -placare also gave us placate. You may ask, what about similar-looking words placid and placebo? These words are related to implacable and placate, but not as closely as you might suspect. They come from the Latin verb placēre, a relative of placare that means "to please."
Origin of implacable
Middle English, from Latin implacabilis, from in- + placabilis placable
First Known Use: 15th century
IMPLACABLE Defined for Kids
Definition of implacable for Students
: impossible to please, satisfy, or change <implacable enemies>
Seen and Heard
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