monoxide

noun

mon·​ox·​ide mə-ˈnäk-ˌsīd 

: an oxide containing one atom of oxygen in a molecule

Examples of monoxide in a Sentence

Recent Examples on the Web

Carbon monoxide can also be created when people use portable generators or run cars in their garages to stay warm or charge their phones. —Jeremy Tanner, The Hill, 21 Jan. 2026

Angie Hicks Ask Angi (TNS) Carbon monoxide (CO) is one of the most serious safety hazards in a home, and one of the easiest to miss. —Tribune News Service, Baltimore Sun, 20 Jan. 2026

The team also detected an arc of sulfur monoxide beyond the dust of the disk, but only on one of its sides. —Robert Lea, Space.com, 12 Jan. 2026

First Alert Combination Smoke & Carbon Monoxide Alarm Carbon monoxide poisoning can be deadly, which is why travelers have been stocking up on best-selling the First Alert Combination Smoke & Carbon Monoxide Alarm this year. —Merrell Readman, Travel + Leisure, 30 Dec. 2025

Word History

Etymology

International Scientific Vocabulary

First Known Use

1868, in the meaning defined above

Phrases Containing monoxide

• carbon monoxide
• chlorine monoxide
• lead monoxide

Rhymes for monoxide

• hydroxide
• tetroxide

Kids Definition

monoxide

noun

mon·​ox·​ide mə-ˈnäk-ˌsīd 

: an oxide containing only one oxygen atom in the molecule

Medical Definition

monoxide

noun

mon·​ox·​ide mə-ˈnäk-ˌsīd 

: an oxide containing one atom of oxygen per molecule see carbon monoxide