noun🔗ShareAn SI/MKS unit of measure, the length of one millionth of a meter. Symbols: µm, um, rm."The scientist used a micrometer to measure the tiny speck of dust. "unitsciencephysicstechnicalmathamountChat with AIVocabulary GamePractice Reading
noun🔗ShareA device used to measure distance very precisely but within a limited range, especially depth, thickness, and diameter."The mechanic used a micrometer to measure the precise thickness of the car's brake rotor. "devicetechnologymachinesciencetechnicalphysicsChat with AIVocabulary GamePractice Reading
