ultramicro

adjective

ul·tra·mi·cro ˌəl-trə-ˈmī-(ˌ)krō

Synonyms of ultramicro next

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: being or dealing with something smaller than micro

Word History

First Known Use

1937, in the meaning defined above

Time Traveler

The first known use of ultramicro was in 1937

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Cite this Entry

Style

“Ultramicro.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ultramicro. Accessed 30 Oct. 2025.

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