ultrathin

adjective
ul·​tra·​thin | \ ˌəl-trə-ˈthin How to pronounce ultrathin (audio) \

Definition of ultrathin

: extremely or extraordinarily thin ultrathin phones ultrathin fashion models The molecules ride on the surface like a film of soap and assemble themselves into an ultrathin layer about one-millionth of an inch thick.— Mike May

First Known Use of ultrathin

1851, in the meaning defined above

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The first known use of ultrathin was in 1851

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Cite this Entry

“Ultrathin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ultrathin. Accessed 4 Aug. 2020.

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ultrathin

adjective
ul·​tra·​thin | \ ˌəl-trə-ˈthin How to pronounce ultrathin (audio) \

Medical Definition of ultrathin

: exceedingly thin ultrathin sections for use in electron microscopy

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