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

This quiet spread reflects the remarkable advancement of synthetic speech technology and its growing adoption across countless applications. — Will Jones, Sacbee.com, 22 Sep. 2026

The same expression was no doubt used by countless Commanders fans who had seen their quarterback miss much of the 2025 season with the same injury to the same elbow. — Chuck Schilken, Los Angeles Times, 21 Sep. 2026

After countless acid trips, Alpert visited an Indian guru who practiced Bhakti yoga. — Claire Hoffman, Rolling Stone, 21 Sep. 2026

Our cult of excellence spans through centuries and is well embodied by people like Leonardo da Vinci, Guglielmo Marconi, Enrico Fermi and countless other pioneers who changed the world with their talent. — Martino Carrera, Footwear News, 21 Sep. 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