countless

adjective

count·​less ˈkau̇nt-ləs 

: too numerous to be counted : myriad, many

countlessly adverb

Synonyms of countless

• many
• numerous
• innumerable
• numberless

Examples of countless in a Sentence

There are countless reasons why that would not be a good idea.

I've been there countless times.

Recent Examples on the Web

The ball bounced off Boone’s mitt and straight into Pete Rose’s glove for an out — a catch played on countless highlight reels through the decades in Philadelphia. — Dan Gelston, Chicago Tribune, 10 Nov. 2026

Thanks to the gold rush, Northern California’s population surged as countless Americans, as well as immigrants from across the globe, arrived to seek their fortune. — Terry Hartle, Christian Science Monitor, 9 Nov. 2026

With countless flavor and color combinations to choose from, frosting is the perfect finishing touch for everything from sugar cookies to layer cakes. — Jessica Safavimehr, Southern Living, 9 Nov. 2026

There are brand dinners, destination shows and off-calendar presentations, store openings, festival takeovers, awards events and countless other celebrity parties, all designed to create a moment and, ideally, keep a brand in the conversation. — Alex Badia, Footwear News, 9 Nov. 2026

Word History

First Known Use

1593, in the meaning defined above

Kids Definition

countless

adjective

count·​less ˈkau̇nt-ləs 

: too numerous to be counted : innumerable