countless
Americanadjective
adjective
Other Word Forms
Etymology
Origin of countless
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."
Vocabulary lists containing countless
Much Ado: Synonyms for "Many"
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Talk Like Shakespeare Day, List 6
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"Dogs at Work"
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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.
The idea that black holes might connect distant regions of the cosmos — or even act as time machines — inspired countless papers, books and films.
From Science Daily • May 22, 2026
A helpful map of the globe points out notoriously treacherous waters, including those off the southern tip of South America, where countless sailors have perished in the turbulent seas around Cape Horn.
From The Wall Street Journal • May 22, 2026
“There are countless New Yorkers desperate to attend a World Cup match, but who simply cannot afford to go.”
From MarketWatch • May 21, 2026
Conversely, the Bible contains countless references to revenge.
From Salon • May 19, 2026
The same words were exchanged countless times that night: “No, I tell you it was Lincoln who was assassinated.”
From "Chasing Lincoln's Killer" by James L. Swanson
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.
