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