Mach number
"mach-number" is a 10-letter English headword indexed on PlainSpell.
The verdict
“Mach number” is uncommon English (outside the top frequency list), classed as a noun. The kind of spelling people second-guess.
- Unranked
- below top-frequency English
- 11
- letters
According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - The ratio of the speed of a body to that of sound in the surrounding medium.
Corpus desk
Index EN-mach-number · Mach number · English
Mach number · unranked · 0 variants · 0 confusables
- FREQ-UNRANKED Unranked
- LEN-MEGA 11 letters
- VOW-3 3 vowels
- CONFUS-0 No pairs
- VAR-0 0 variants
- BOOK-THIN "M" thin
- PHOTO-UNK Peer pending
Read with this headword: Spelling guide for this pattern
Desk codes from Wiktionary headword shape, FrequencyWords rank tier, confusable-pair count, generated misspelling depth, letter-cohort book size, and photo-finish peer. Not a difficulty grade.
| Property | Value |
|---|---|
| Headword | Mach number |
| Language | English |
| Part of speech | Noun |
| Letters | 11 |
| Misspellings tracked | 0 |
| Confusable pairs | 0 |
| Source | Wiktionary (kaikki.org) |
Long-tail rank of “Mach number” in English
Rare enough to double-check
Mach number is uncommon English outside the top frequency list, classed as anoun. Rarity is why readers land here mid-draft. Gloss: "The ratio of the speed of a body to that of sound in the surrounding medium.".
We couldn't generate a plausible misspelling set for Mach number, a straightforward case of a spelling with little room for common typos. This headword has no recorded confusable partner, which usually means its spelling is distinct enough that readers don't reach for a similar-looking word instead.
Etymologically, the entry records: After physicist Ernst Mach. The correct English form is Mach number, spelled M-A-C-H- -N-U-M-B-E-R.
Definition
- 1The ratio of the speed of a body to that of sound in the surrounding medium.
Etymology
After physicist Ernst Mach.
Definitions, pronunciation, and etymology for this entry are drawn from Wiktionary via the kaikki.org structured extract (CC BY-SA). See the methodology for how each field is sourced and updated.