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Synonyms

countless

American  
[kount-lis] / ˈkaʊnt lɪs /

adjective

  1. too numerous to count; innumerable.

    the countless stars.

    Synonyms:
    unlimited, myriad, endless, numberless

countless British  
/ ˈkaʊntlɪs /

adjective

  1. innumerable; myriad

"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

Other Word Forms

  • countlessly adverb

Etymology

Origin of countless

First recorded in 1580–90; count 1 + -less

Explanation

Countless means more than you could possibly count. If you have countless reasons why you love living in New York, there are so many reasons that you can't list them all. Countless is a good adjective to use when you want to emphasize how endless, huge, or immeasurable something is. Your could say that smoke detectors save countless lives each year, or that your principal has tried countless times to ban soda at school, only to be outvoted by the student council over and over. The word dates from the 16th century, from the verb count, with its Old French root, conter, "add up."

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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.

He has engaged in countless bilateral forums, work groups and discussions about immigration, drug trafficking, cross-border commerce and other concerns, and generally received good marks from U.S. officials.

From Los Angeles Times • Apr. 14, 2026

All of these things, along with countless more, are worth it — the extra minutes they take, the care, the discernment, the near-constant monitoring.

From Salon • Apr. 13, 2026

In a post on X, he said her "extraordinary musical journey" enriched the nation's cultural heritage and touched "countless hearts across the world".

From BBC • Apr. 12, 2026

But there were countless other people, their names lost to history, who built the institutions that strengthened early American communities and promoted human flourishing.

From The Wall Street Journal • Apr. 10, 2026

The viselike pressure of countless tons of water above compressed me from every direction, and my lungs were full of agonizing fire.

From "City of the Plague God" by Sarwat Chadda