ther·​mos | \ˈthər-məs \

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

At least three sets of mate gourds and thermoses sat untouched on the coffee table. Candace Rose Rardon, Longreads, "The Country Where Fútbol Comes First," 10 July 2018 And one of the walk-up food locations is a lunch pail that’s been propped up with a giant thermos. Mekado Murphy, New York Times, "Walk Among Giants — Woody Included — at Disney World's New Toy Story Land," 28 June 2018 The restaurant is in the shape of a giant lunch box, including an old-school thermos. Gabrielle Russon,, "Disney Toy Story Land first look: Details bring attraction to life," 28 June 2018 Those who wanted more calm spread their prayer rugs and mats on a drying barley field behind the camp and sat there, sipping coffee and tea they from thermos bottles. Washington Post, "Gaza protests driven by desperation, Hamas organization," 4 Apr. 2018 There’s a hammock with two people in it, a thermos next to a beach towel and a radio playing country music as kayaks bob across the lake a few hundred feet away. Rachel Jones, charlotteobserver, "He's Mecklenburg's only wildlife officer in a county with over 1 million people," 28 June 2018 From left: pockets stacked on top of pockets at Junya Watanabe; Louis Vuitton’s luggage legacy repackaged as a vest, care of Virgil Abloh; a coat featuring two pockets that could fit a pre-work thermos and a post-work beer at OAMC. Jacob Gallagher, WSJ, "The Newest Men’s Clothing Trends to Follow (or Laugh At)," 28 June 2018 Make sure to bring warm clothes, a blanket or chair to sit in, and maybe even a thermos filled with tea or hot chocolate. Avery Thompson, Popular Mechanics, "Enjoy a Cool Space Show Tonight When the Delta Aquarids Meteor Shower Appears," 28 July 2016 The weaponized silliness results in some painful pratfalls, including one character’s plunge from an apartment fire escape and, later, having a thermos of hot coffee thrown in his face. Ann Hornaday, kansascity, "A game cast makes good-natured ‘Tag’ a fun time," 14 June 2018

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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Statistics for thermos

Last Updated

16 Sep 2018

Look-up Popularity

Time Traveler for thermos

The first known use of thermos was in 1907

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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 \

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

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More from Merriam-Webster on thermos

See words that rhyme with thermos

Spanish Central: Translation of thermos

Nglish: Translation of thermos for Spanish Speakers

Comments on thermos

What made you want to look up thermos? Please tell us where you read or heard it (including the quote, if possible).


playful or foolish behavior

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