Standard Lemma guide

micrometre

noun · 1 senses · updated from the 2026-07-25 local source snapshot

Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.

Sound

Pronunciation

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  • Received-Pronunciation: /ˈmaɪkɹəˌmiːtə/
  • General-American: /ˈmaɪkɹəˌmitəɹ/

1

noun

Meaning 1

An SI and mks unit of measure, the length of one-millionth of a metre. Symbol: μm, um, μ.

Definition source: English Wiktionary via Wiktextract

Examples

  • Holonyms: millimetre < centimetre < decimetre < metre < kilometre < megametre < gigametre < terametre < petametre
  • Meronyms: picometre < nanometre

Meaning relationships

Synonyms: micron

Antonyms: none provided

History

Etymology

Etymology tree Proto-Indo-European *mey-der.? Ancient Greek μῑκρός (mīkrós) Ancient Greek μῑκρο- (mīkro-)lbor. English micro- English metre English micrometre From micro- + metre.