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noun

thermos

THUR-mos

Thermos (noun) means an insulated flask that keeps drinks or food hot or cold. Example: “She packed a thermos of coffee for the road trip.”

noun
1
An insulated flask that keeps drinks or food hot or cold.
"She packed a thermos of coffee for the road trip."

How to use thermos

Learner’s notes

In plain EnglishA vacuum-sealed flask that keeps drinks hot or cold for hours.

Common mistake

Originally a brand name; now used generically for any insulated flask, similar to "hoover" for vacuum cleaners.

Common pairings
a thermos of tea thermos flask

Word forms

thermoses plural, thermoi plural, thermoi plural

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She packed a _____ of coffee for the road trip.

Etymology

Originally a trademark, from Greek thermos ("warm, hot").

Origin: Greek

thermos flask thermos bottle

Frequently asked questions

What does “thermos” mean?

The word “thermos” means an insulated flask that keeps drinks or food hot or cold. In plain terms, a vacuum-sealed flask that keeps drinks hot or cold for hours.

How do you pronounce “thermos”?

“Thermos” is pronounced THUR-mos (/ˈθɝ.məs/ in IPA).

How do you use “thermos” in a sentence?

Here is “thermos” used in a sentence: “She packed a thermos of coffee for the road trip.”

What part of speech is “thermos”?

“Thermos” is a noun.

Where does the word “thermos” come from?

The word “thermos” comes from Greek. Originally a trademark, from Greek thermos ("warm, hot").

Definitions: FreeDict original editorial