Phrase guide

atomic mass unit

noun · 2 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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No pronunciation record was provided for this word.

1

noun

Meaning 1

A unit of mass equal to 1/12 the mass of an atom of 12C (carbon-12, an isotope of carbon).

Definition source: English Wiktionary via Wiktextract

Usage: physical

Topics: chemistry, natural-sciences, physical-sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

2

noun

Meaning 2

unit of mass for expressing masses of atoms or molecules

Definition source: Princeton WordNet 3.0

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

Broader terms: mass unit

History

Etymology

No etymology was provided for this word.

Across languages

Translations

11 source translations are retained for this English entry.

  • Chinese Mandarin: 原子質量單位 /原子质量单位 (yuánzǐ zhìliàng dānwèi) — a unit of mass equal to 1/12 the mass of an atom of the 12C isotope of carbon
  • Finnish: atomimassayksikkö — a unit of mass equal to 1/12 the mass of an atom of the 12C isotope of carbon
  • Hungarian: atomi tömegegység — a unit of mass equal to 1/12 the mass of an atom of the 12C isotope of carbon
  • Indonesian: satuan massa atom — a unit of mass equal to 1/12 the mass of an atom of the 12C isotope of carbon
  • Irish: aonad maise adamhaí — a unit of mass equal to 1/12 the mass of an atom of the 12C isotope of carbon
  • Malay: unit jisim atom — a unit of mass equal to 1/12 the mass of an atom of the 12C isotope of carbon
  • Polish: jednostka masy atomowej — a unit of mass equal to 1/12 the mass of an atom of the 12C isotope of carbon
  • Portuguese: unidade de massa atômica — a unit of mass equal to 1/12 the mass of an atom of the 12C isotope of carbon
  • Portuguese: u.m.a. — a unit of mass equal to 1/12 the mass of an atom of the 12C isotope of carbon
  • Tagalog: isahin ng mulpikning bugat — a unit of mass equal to 1/12 the mass of an atom of the 12C isotope of carbon
  • Vietnamese: đơn vị khối lượng nguyên tử — a unit of mass equal to 1/12 the mass of an atom of the 12C isotope of carbon