Phrase guide

Mach number

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 ratio of the speed of a body to that of sound in the surrounding medium.

Definition source: English Wiktionary via Wiktextract

Usage: uncountable

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

the ratio of the speed of a moving body to the speed of sound

Definition source: Princeton WordNet 3.0

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

Broader terms: ratio

History

Etymology

After physicist Ernst Mach.

Across languages

Translations

18 source translations are retained for this English entry.

  • Catalan: nombre de Mach — ratio — see also Mach
  • Chinese Mandarin: 馬赫數 /马赫数 — ratio — see also Mach
  • Czech: Machovo číslo — ratio — see also Mach
  • Dutch: machgetal — ratio — see also Mach
  • Estonian: Machi arv — ratio — see also Mach
  • Finnish: Machin luku — ratio — see also Mach
  • German: Mach-Zahl — ratio — see also Mach
  • Greek: αριθμός Μαχ (arithmós Mach) — ratio — see also Mach
  • Italian: numero di Mach — ratio — see also Mach
  • Japanese: マッハ数 (mahha sū) — ratio — see also Mach
  • Kannada: ಮ್ಯಾಕ್ ಸಂಖ್ಯೆ (myāk saṅkhye) — ratio — see also Mach
  • Korean: 마하수 (mahasu) — ratio — see also Mach
  • Portuguese: número de Mach — ratio — see also Mach
  • Portuguese: número Mach — ratio — see also Mach
  • Romanian: numărul lui Mach — ratio — see also Mach
  • Spanish: número Mach — ratio — see also Mach
  • Thai: เลขมัค — ratio — see also Mach
  • Turkish: Mach sayısı — ratio — see also Mach