Definition of coolant
: a usually fluid cooling agent
Recent Examples of coolant from the Web
In the coolant system, a valve closed, causing water pressure to build.
A pre-dawn accident at the plant in 1979 enabled nuclear reactor coolant to escape, causing the core to overheat.
The coolant is 80 percent water mixed with antifreeze, anti-bacterial agents and corrosion inhibitors.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'coolant'. Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
First Known Use of coolant
COOLANT Defined for English Language Learners
Definition of coolant for English Language Learners
: a liquid that is used to cool an engine or machine
Seen and Heard
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