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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.

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 August of 2024, I walked the Himalayan ranges of Venice with Dennis Hathaway and his wife, Laura Silagi, who had taken a hard fall on one of their neighborhood’s countless volcanic sidewalks.

From Los Angeles Times • Apr. 11, 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

With countless awards to his name, he leaves a legacy of photos and footage that will see him remembered as one of the pioneers of wildlife filmmaking.

From BBC • Apr. 10, 2026

Nowadays, of course, “alma mater” is what people call the place where they went to school and, one hopes, were fed countless yummy bites of knowledge from a vast and scrumptious buffet of education.

From "The Unseen Guest" by Maryrose Wood