ul·​tra·​mi·​cro ˌəl-trə-ˈmī-(ˌ)krō How to pronounce ultramicro (audio)
: 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

Dictionary Entries Near ultramicro

Cite this Entry

“Ultramicro.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ultramicro. Accessed 9 Jun. 2023.

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