noun, often capitalized
dew·​ar | \ ˈdü-ər How to pronounce dewar (audio) also ˈdyü- \

Definition of dewar

 (Entry 1 of 2)

: a glass or metal container made like a vacuum bottle that is used especially for storing liquefied gases

called also Dewar flask


biographical name
Dew·​ar | \ ˈdü-ər How to pronounce Dewar (audio) , ˈdyü- \

Definition of Dewar (Entry 2 of 2)

Sir James 1842–1923 Scottish chemist and physicist

Examples of dewar in a Sentence

Recent Examples on the Web: Noun Dewar needed a container that would resist changes in temperature, keeping his cold fluid cold without need for refrigerating equipment. Patrick Di Justo, WIRED, "Science of BSG: Why So Sweaty on Demetrius?," 14 May 2008

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

First Known Use of dewar


1939, in the meaning defined above

History and Etymology for dewar


Sir James Dewar

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The first known use of dewar was in 1939

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Cite this Entry

“Dewar.” The Dictionary, Merriam-Webster Inc., Accessed 14 December 2019.

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Rhyming Dictionary: Words that rhyme with dewar

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