Phrase guide

rest mass

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

The mass of a body when it is not moving relative to an observer.

Definition source: English Wiktionary via Wiktextract

Topics: natural-sciences, physical-sciences, physics

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

2

noun

Meaning 2

(physics) the mass of a body as measured when the body is at rest relative to an observer, an inherent property of the body

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

History

Etymology

No etymology was provided for this word.

Across languages

Translations

20 source translations are retained for this English entry.

  • Armenian: հանգստի զանգված (hangsti zangvac) — mass of a body when it is not moving
  • Catalan: massa en repòs — mass of a body when it is not moving
  • Chinese Mandarin: 靜止質量 /静止质量 (jìngzhǐ zhìliàng) — mass of a body when it is not moving
  • Danish: hvilemasse — mass of a body when it is not moving
  • Finnish: lepomassa — mass of a body when it is not moving
  • French: masse au repos — mass of a body when it is not moving
  • German: Ruhemasse — mass of a body when it is not moving
  • Hungarian: nyugalmi tömeg — mass of a body when it is not moving
  • Italian: massa a riposo — mass of a body when it is not moving
  • Italian: massa invariante — mass of a body when it is not moving
  • Italian: massa intrinseca — mass of a body when it is not moving
  • Polish: masa spoczynkowa — mass of a body when it is not moving
  • Portuguese: massa invariante — mass of a body when it is not moving
  • Russian: ма́сса поко́я (mássa pokója) — mass of a body when it is not moving
  • Spanish: masa invariante — mass of a body when it is not moving
  • Spanish: masa en reposo — mass of a body when it is not moving
  • Turkish: değişmez kütle — mass of a body when it is not moving
  • Turkish: durgun kütle — mass of a body when it is not moving
  • Turkish: gerçek kütle — mass of a body when it is not moving
  • Turkish: tam kütle — mass of a body when it is not moving