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Synonyms

implacable

American  
[im-plak-uh-buhl, -pley-kuh-] / ɪmˈplæk ə bəl, -ˈpleɪ kə- /

adjective

  1. not to be appeased, mollified, or pacified; inexorable.

    an implacable enemy.

    Synonyms:
    merciless, unbending, unappeasable

implacable British  
/ ɪmˈplækəbəl /

adjective

  1. incapable of being placated or pacified; unappeasable

  2. inflexible; intractable

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Synonym Usage

See inflexible.

Other Word Forms

Etymology

Origin of implacable

First recorded in 1375–1425; late Middle English word from Latin word implācābilis. See im- 2, placable

Explanation

An implacable person just can’t be appeased. If you really offended your best friend and tried every kind of apology but she refused to speak to you again, you could describe her as implacable. Implacable is derived from the verb to placate, which means to soothe, or to appease. If you’re babysitting and the kid starts screaming the moment that his parents leave the house, and nothing you give him, be it a toy or ice cream, can calm him down, he might seem implacable. But try the TV. It tends to turn screaming kids into silent, happy zombies.

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Vocabulary lists containing implacable

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Supreme Court historically used Asian Americans’ supposedly implacable foreignness to justify greater, institutionally enforced apartness.

From Slate • May 26, 2026

If she’s not in cahoots with the unnervingly blasé doctor, she’s at least in agreement with the implacable timetable he’s laid out.

From Los Angeles Times • May 13, 2026

The implacable fourth-wicket pair took full advantage of a pitch that just got better and better for batting.

From BBC • Apr. 6, 2026

I felt sickened by every piece of news I gave her—her court date canceled, the border closed, the pandemic spreading—but her faith in the system, and in me, seemed implacable.

From Slate • Jan. 15, 2026

But Svadilfari was sure-footed and implacable, even in the thickest, wettest mud, and he hauled the rocks to Asgard, although the stone-boat was so heavy it cut deep gashes into the sides of the hills.

From "Norse Mythology" by Neil Gaiman

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