mortal enemy

noun

: someone one hates very much and for a long time

They've been mortal enemies for many years.

Examples of mortal enemy in a Sentence

Recent Examples on the Web

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.

Maybe death at the hands of your mortal enemy doesn’t need to be quick and painless. — Amanda Whiting, Vulture, 29 June 2026 For the one whose mortal enemy is humidity. — Jeaneen Russell, PEOPLE, 15 Nov. 2025 And many in the Make America Healthy Again movement led by Kennedy consider glyphosate to be a mortal enemy. — Alex Hogan, STAT, 26 Feb. 2026 Tens of millions of Russians, including senior officials and many of the country’s wealthiest people, now view the West as a mortal enemy. — Alexander Gabuev, Foreign Affairs, 17 Apr. 2025 See All Example Sentences for mortal enemy

Cite this Entry

Style

“Mortal enemy.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mortal%20enemy. Accessed 8 Jul. 2026.

Copy Citation

mortal enemy

noun

Examples of mortal enemy in a Sentence

Browse Nearby Words

Cite this Entry

More from Merriam-Webster

Word of the Day

gambol

Popular in Grammar & Usage

Is that lie 'bald-faced' or 'bold-faced'?

'A' or 'an'? What about before 'h'? An Indefinite Article Guide

Why is '-ed' sometimes pronounced at the end of a word?

Commonly Misspelled Words

How to Use Em Dashes (—), En Dashes (–) , and Hyphens (-)

Popular in Wordplay

14 Phobias You Probably Haven't Heard Of

The Longest Long Words List

One-Word Oxymorons: Bittersweet, Spendthrift, and More

Ten Words Ending with a Silent ‘T’

12 Lovely and Unusual Words for the Natural World

Popular

Is that lie 'bald-faced' or 'bold-faced'?

14 Phobias You Probably Haven't Heard Of

The Longest Long Words List

Games & Quizzes