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Definitions

quaternary

[kwot-er-ner-ee, kwuh-tur-nuh-ree] / ˈkwɒt ərˌnɛr i, kwəˈtɜr nə ri /
ADJECTIVE
four
Synonyms
STRONG
quadruple quadruplicate tetrad
WEAK
quadrigeminal quadripartite quadrivial quaternate
NOUN
four
Synonyms
STRONG
quadrivium quadrumvirate quadruple quadruplet quadruplets quartet quartette quaternion quaternity tetrad tetralogy
WEAK
quadrigeminal quadripartition

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.

Sunway Healthcare operates its flagship quaternary hospital in Kuala Lumpur, Malaysia’s capital.

From The Wall Street Journal • Feb. 6, 2026

Sunway Healthcare operates its flagship quaternary hospital in Kuala Lumpur, the country’s capital.

From The Wall Street Journal • Nov. 5, 2025

Since quaternary ammonium compounds are present in many personal-care products and disinfectants, which are being used more frequently since the COVID-19 pandemic began, humans are regularly exposed to these chemicals.

From Science Daily • Mar. 25, 2024

The Salyerses’ unusual marriage is known as a quaternary marriage, and their sons are known as quaternary twins.

From Washington Post • Aug. 24, 2022

Originally, geological history was divided into four spans of time: primary, secondary, tertiary, and quaternary.

From "A Short History of Nearly Everything" by Bill Bryson

From Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.