implacable
Americanadjective
adjective
-
incapable of being placated or pacified; unappeasable
-
inflexible; intractable
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.
Vocabulary lists containing implacable
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Grade 11, List 3
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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
Lee Marvin plays an implacable man out for vengeance in this 1967 thriller, arriving in a 4K restoration, that keeps the audience at a cool remove.
From The Wall Street Journal • Apr. 15, 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
García Harfuch — always decked out in suit and tie — transmits an aura of competence, and his media-savvy advisors have burnished his image as an implacable foe of the cartels.
From Los Angeles Times • Nov. 29, 2025
It is a great story now of implacable vengeance and tragic passions and inevitable doom.
From "Mythology: Timeless Tales of Gods and Heroes" by Edith Hamilton
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.