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

In March, K-9 dog Bettie helped agents discover a thermos stuffed with 2 pounds of pork belonging to a passenger on a flight from China. Eliza Fawcett,, "‘We see meats of all kinds’: U.S. customs agents say seizure of African rodent meat at O’Hare not outlandish," 3 July 2019 Grab a tumbler of cold brew the size of your head. Sling a thermos of your best Italian brew over your shoulder. Michelle Santiago Cortés,, "Krispy Kreme Wants To Give You A Free Doughnut Tomorrow – No Strings Attached," 7 June 2019 Fill the thermos since June 10 is National Iced Tea Day. Ron Browning,, "Havre de Grace: First Friday and Jazz & Blues Fest highlight weekend," 6 June 2019 Photo: Nona Lim Campbell launched its drinkable soups after researchers noticed that parents sometimes poured soup into thermos containers to drink in their cars or microwaved it in mugs while working from home. Anne Marie Chaker, WSJ, "Put Down That Spoon—This Soup Is For Drinking," 5 Jan. 2019 This tough thermos was a champ at keeping liquid warm for hours in our tests. Betty Gold, Good Housekeeping, "The Best Travel Coffee Mugs That Won't Leak or Spill," 6 Mar. 2018 For always-ready hot chocolate or coffee, pack a double-wall vacuum insulated thermos with a leakproof lid. Clint Carter, WSJ, "Never Camped in the Snow? You’re Missing Out.," 11 Dec. 2018 Class schedule in one hand and a warm thermos of coffee in the other. Katelyn Chef, Teen Vogue, "Best Thermoses and Tumblers for Back to School," 10 Aug. 2018 Also, merch is normal for high-end automakers — BMW sells hats, thermoses, luggage, and… $61 golf balls. Elizabeth Lopatto, The Verge, "Elon Musk’s Teslaquila is actually a good idea," 19 Oct. 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

8 Jul 2019

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 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

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More from Merriam-Webster on thermos

Rhyming Dictionary: 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).


appealing forcibly to the mind or reason

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