Bible Dictionaries
Millimicron

Webster's Dictionary

(n.) The thousandish part of a micron or the millionth part of a millimeter; - a unit of length used in measuring light waves, etc.

Bibliography Information
Webster, Noah. Entry for 'Millimicron'. Noah Webster's American Dictionary. https://www.studylight.org/​dictionaries/​eng/​web/​m/millimicron.html. 1828.