thermos

noun

ther·​mos ˈthər-məs How to pronounce thermos (audio)
: a container (such as a bottle or jar) with a vacuum between an inner and outer wall used to keep material and especially liquids either hot or cold for considerable periods

Examples of thermos in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
These sound like guys who show up with a thermos, and a sandwich wrapped in wax paper. — Mark Glende, Twin Cities, 3 Apr. 2026 Coffee arrived at my door in a Yeti thermos. — Stacey Leasca, Travel + Leisure, 2 May 2026 Students are asked to bring Tupperware containers and a thermos to take food and drinks home at the end of each day. — Lauren Schuster, Kansas City Star, 23 June 2026 On winter evenings even Oslo, locals head into the forest after work with headlamps and thermoses. — David Nikel, Forbes.com, 27 Feb. 2026 See All Example Sentences for thermos

Word History

Etymology

from Thermos, a trademark

First Known Use

1907, in the meaning defined above

Time Traveler
The first known use of thermos was in 1907

Rhymes for thermos

See All Rhymes for thermos

Browse Nearby Words

thermoremanent
thermos
thermoscopic
See all Nearby Words

Cite this Entry

“Thermos.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/thermos. Accessed 7 Jul. 2026.

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Kids Definition

thermos

noun
ther·​mos ˈthər-məs How to pronounce thermos (audio)
: a container (as a bottle) with a vacuum between an inner and an outer wall used to keep material (as liquids) hot or cold

More from Merriam-Webster on thermos

Nglish: Translation of thermos for Spanish Speakers

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