im·​pla·​ca·​ble (ˌ)im-ˈpla-kə-bəl How to pronounce implacable (audio) -ˈplā- How to pronounce implacable (audio)
: not placable : not capable of being appeased, significantly changed, or mitigated
an implacable enemy
implacability noun
implacably adverb

Did you know?

Implacable is rooted in Latin placare, meaning "to soothe," but its im- prefix is a variant of the negating prefix in- (as in inactive) and it signals that there’s nothing warm and fuzzy here. Someone or something described as implacable cannot be soothed, which usually means trouble: implacable is most often attached to words like foe, enemy, hatred and hostility. The opposite of implacable is, of course, placable; it means "easily soothed," but sadly isn’t called upon very often. Another placare word is likely more familiar. Placate means "to soothe or appease"; it’s frequently applied when an angry person is made to feel less so.

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
Recent Examples on the Web Rather, China is now looking at a Taiwan in which Beijing’s most implacable political foe, the DPP, is electorally diminished. Nick Frisch, Foreign Affairs, 16 May 2024 But at the Hudson Theatre, where the revival has been enjoying its status as the season’s must-see hit (after a triumphant run off-Broadway at New York Theatre Workshop), the biting wit and thinly disguised rage coexist with implacable affection. Charles McNulty, Los Angeles Times, 29 May 2024 Image Image Image One of his questions was about light itself — the beautiful, implacable science of it, how wavelengths and densities affect our perception. Siddhartha Mitter, New York Times, 10 May 2024 An implacable observation, as France seemed far from the level of the best nation in the world currently. Assile Toufaily, Forbes, 28 Feb. 2024 See all Example Sentences for implacable 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'implacable.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


Middle English, from Latin implacabilis, from in- + placabilis placable

First Known Use

15th century, in the meaning defined above

Time Traveler
The first known use of implacable was in the 15th century


Dictionary Entries Near implacable

Cite this Entry

“Implacable.” Dictionary, Merriam-Webster, Accessed 23 Jun. 2024.

Kids Definition


im·​pla·​ca·​ble (ˈ)im-ˈplak-ə-bəl How to pronounce implacable (audio) -ˈplā-kə- How to pronounce implacable (audio)
: not possible to please, satisfy, or change
an implacable enemy
implacability noun
-ˈplak-ə-blē How to pronounce implacable (audio)

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