ther·​mos | \ ˈthər-məs How to pronounce thermos (audio) \

Definition of thermos

: 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 Savvy shoppers in 2021 have religated the folding chair to the garage and the thermos to the cupboard. Kirby Adams, The Courier-Journal, 17 Nov. 2021 Ballinger recommends bringing a small thermos with hot tea or bone broth and water bottles that can fit inside your pack, so their contents won’t freeze. Washington Post, 12 Nov. 2021 The electricity is out, so Hazel is forced to serve tea from a thermos. Los Angeles Times, 8 Nov. 2021 Unlike my stainless steel thermos, the cup easily collapsed into a round disk small enough to fit in the pockets of our Navy Working Uniforms. Bon Appétit, 4 Nov. 2021 Invest in a thermos—this is the most important one. Quartz Staff, Quartz, 1 Nov. 2021 The coffee was issued from a battered old thermos and drunk from tin cups, the old thin-walled ones that transfer the heat to your hand. Steve Meyer, Anchorage Daily News, 18 Sep. 2021 The early start and short, cold walk in the dark, draped in blankets and clutching a thermos of coffee, were more than worth it to have the mountain seemingly to ourselves. Nina Caplan, Travel + Leisure, 14 Sep. 2021 The musician, who sipped from a thermos full of herbal tea, contemplated the song’s lyrics. Adam Iscoe, The New Yorker, 16 Aug. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'thermos.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of thermos

1907, in the meaning defined above

History and Etymology for thermos

from Thermos, a trademark

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Time Traveler for thermos

Time Traveler

The first known use of thermos was in 1907

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Statistics for thermos

Last Updated

27 Nov 2021

Cite this Entry

“Thermos.” Dictionary, Merriam-Webster, Accessed 3 Dec. 2021.

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More Definitions for thermos



English Language Learners Definition of thermos

: a container that keeps liquids hot or cold for long periods of time


ther·​mos | \ ˈthər-məs How to pronounce thermos (audio) \

Kids Definition of thermos

: a container (as a bottle or jar) that has a vacuum between an inner and an outer wall and is used to keep liquids hot or cold for several hours

More from Merriam-Webster on thermos

Nglish: Translation of thermos for Spanish Speakers


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