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Synonyms

mercilessly

American  
[mur-si-lis-lee] / ˈmɜr sɪ lɪs li /

adverb

  1. without mercy, pity, or tolerance.

    I was mercilessly bullied in school throughout my childhood.

    Any speaker who goes on longer than 15 minutes will be interrupted mercilessly by the moderator.

  2. without reprieve; unbearably.

    An unusually humid July morning had morphed into a mercilessly hot afternoon.


Etymology

Origin of mercilessly

merciless ( def. ) + -ly

Explanation

To behave mercilessly is to act without showing pity or sympathy, like a bully who torments other kids or a basketball team that beats the opponent 125 – 0. Whenever possible, it’s best to avoid people who act mercilessly. When you show mercy, you're kind and empathetic. Without any mercy, you’re merciless, and when you act this way you act mercilessly. You show no pity! Some big brothers kid their little sisters mercilessly, and a judge who gives the maximum sentence for a minor crime has ruled mercilessly. Mercy is at the root of mercilessly, from the Old French merci, which means both "thanks" and "pity." If people act mercilessly, tell them thanks for nothing!

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Vocabulary lists containing mercilessly

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.

See Examples For:

Mohammad Mahfouz Alam, who sells footwear from a stall nearby, said on hot days like these, there's little respite as the heat rises from the ground up and the sun beats down mercilessly from above.

From BBC ● Jun. 15, 2026

Brunson, hounded mercilessly by the Spurs, didn't make a basket until the second quarter.

From Barron's ● Jun. 11, 2026

The private equity model has struck again—this time, even more quickly and mercilessly than usual.

From Slate ● Jan. 23, 2026

Software stocks have been mercilessly battered in recent weeks, and that trend has continued in a striking way to start this year.

From MarketWatch ● Jan. 17, 2026

By 2011, the West African black rhino was officially declared extinct, thanks to poachers who mercilessly killed them for their horns—which people then use for decorative carvings and grind into powder for medicines.

From "Camp Panda" by Catherine Thimmesh

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