amicron

noun

ami·​cron

(ˈ)āˈmīˌkrän sometimes -mi- or -krən

plural -s

: one of the smallest particles detectable with the ultramicroscope (about 1×10⁻⁷ cm in diameter)

Word History

Etymology

International Scientific Vocabulary a- entry 2 + micron, originally formed as German amikron

First Known Use

circa 1906, in the meaning defined above

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