A vacuum bottle used to keep beverages hot or cold.(noun)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "thermos" in a sentence
"The lid of the thermos is an isolated seal, the normal jar comes with a screwtop."
"For a minimalist this guy seems to really like having every color tank top available, even coffee. but maybe that is an actual coffee tank, aka thermos? not to mention his veritible calvelcade of neckways tank, V, crew. also, I like the way he qualifies his wallet as a minimalist wallet. is a wallet really such a big extravagance?"
"If you are working through lunch, Pimm's in your thermos is a guerrilla tactic for sneaking summer into the office - or homemade lemonade for the responsible."