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

While Louis created countless memorable costumes for the screen, his legacy remains forever entwined with Monroe’s illusion gown. — Seth Abramovitch, HollywoodReporter, 16 Aug. 2026

Neurosurgery is a profound team endeavor, with countless individuals, often unseen, uniting daily to deliver transformative patient outcomes. — Richard Menger Md Mpa, Forbes.com, 15 Aug. 2026

While hibiscus flowers might look tropical—and many varieties thrive in tropical climates—countless other hibiscus varieties grow well in temperate climates. — Shelby Vittek, The Spruce, 15 Aug. 2026

Healthy Ways to Serve Rotisserie Chicken Rotisserie chicken works well as the protein base for countless healthy meals. — Lynn Andriani, Martha Stewart, 15 Aug. 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