mi‧crom‧e‧tre  British English, 
micrometer American English /ˈmaɪkrəʊˌmiːtə $ -kroʊˌmiːtər/ (
also mi‧cron /ˈmaɪkrɒn $ -krɑːn/)
 noun [countable][
Date: 1800-1900; 
Language: Modern Latin; 
Origin: Greek, from mikros 'small']
 a unit for measuring length. There are one million micrometres in one metre. 
 [TahlilGaran] Dictionary of Contemporary English ▲