coolant

noun

cool·​ant ˈkü-lənt 

: a usually fluid cooling agent

Examples of coolant in a Sentence

Recent Examples on the Web

Keeping coolant levels topped off, checking belts and hoses, and ensuring your engine isn’t overheating all contribute to overall performance, including the air conditioning system. — Jessica Safavimehr, Southern Living, 20 July 2026

This cross-shaped cross-section increases the specific surface area available for thermal transfer, enhancing the rate of heat conduction from the core to the coolant. — Aman Tripathi, Interesting Engineering, 19 July 2026

Beyond this, next generation reactor technologies, several of which are being deployed, use coolants such as helium, molten salt, and liquid metal instead of water. — Scott Montgomery, Forbes.com, 17 July 2026

Higher river temperatures are also affecting France’s nuclear plants, which require water as a coolant. — Tim Lister, CNN Money, 11 July 2026

Word History

Etymology

cool entry 2 + -ant entry 1

First Known Use

1915, in the meaning defined above

Rhymes for coolant

• puberulent
• pulverulent

Kids Definition

coolant

noun

cool·​ant ˈkü-lənt 

: a usually fluid cooling substance