chemical warfare

noun

: tactical warfare using substances (such as incendiary mixtures, smoke, or gases) with irritant, burning, poisonous, or asphyxiating properties

There were other isolated instances of chemical warfare. The Greeks used a gas attack with sulphur fumes at the siege of Delium in 424 B.C.

—Bernard Brodie and Fawn M. Brodie

The forswearing of chemical warfare by the major combatants in World War II foreshadowed the later nuclear "balance of terror," during the Cold War.

—Clifford F. Beal

Examples of chemical warfare in a Sentence

Recent Examples on the Web

In Iran and Iraq, survivors of chemical warfare still suffer. — Målfrid Braut-Hegghammer, Foreign Affairs, 7 May 2013

Future bots could help design and carry out biological, nuclear, and chemical warfare. — Matteo Wong, The Atlantic, 27 Apr. 2026

Exposure to chemical warfare agents—such as nerve gas—or to pyridostigmine bromide, a drug given to soldiers as a preventive measure against chemical attacks, may have played a role. — Aliss Higham, MSNBC Newsweek, 21 Oct. 2025

The attack on the oil depots could be construed as chemical warfare, which violates international law, because the aggressors likely knew the hazards the civilians who live in Tehran would face, Cleetus said. — Julia Jacobo, ABC News, 10 Mar. 2026

Word History

First Known Use

1910, in the meaning defined above

Rhymes for chemical warfare

• extraordinaire
• multimillionaire
• abwehr
• affair
• affaire
• airfare
• altair
• armchair
• aware
• beware
• bugbear
• carfare

Medical Definition

chemical warfare

noun

: tactical warfare using incendiary mixtures, smokes, or irritant, burning, poisonous, or asphyxiating gases