nmvsnopWhich spelling fits?

Quick tell: nm is a symbol, nop is a noun, so they fill different roles in a sentence.

Which to use

“nm” is a symbol and “nop” is a noun - they look or sound alike but fill different roles in a sentence.

#22,954
“nm” frequency rank
#49,823
“nop” frequency rank
72777
confusion score

Side-by-Side Comparison

Feature nm nop
Definition Symbole du nanomètre, unité de mesure de longueur du Système international (SI), valant 0,000000001 mètre (10⁻⁹ mètre). Relief, nervure.

Letter map: nm vs nop

Shared letters muted; letters that set nm and nop apart highlighted. Shared run: 1. nm runs 2 letters (CC) against nop's 3 (CVC) - the length gap alone is often enough to separate them once you know to check it.

2 ch
nm
3 ch
nop

Role in the sentence - nm and nop

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: nm is asymbol and nopanoun. On the page they differ by 1 letter(s) in length. Our composite confusion score for this pair is 72777, derived from the frequency rank of both members and their visual similarity.

nm is recorded at frequency rank #22,954, classified as asymbol. nop is at rank #49,823, tagged as anoun.

Glosses for this pair are partially populated in our dataset, but the full side-by-side definitions above should still guide you to the right choice.

With a confusion score of 72777, this pair ranks #42,799 of 440,172 scored French confusable pairs - among the most confusable pairs.

Orthographic DNA of nm vs nop

Shared letters: n. Private to "nm": m. Private to "nop": op.

"nm" · 2 letters · shape CC  ·  "nop" · 3 letters · shape CVC

Frequently Asked Questions

Is swapping "nm" for "nop" ever safe?
No - they are not even the same part of speech. "nm" is a symbol and "nop" a noun, so a sentence built for one is usually ungrammatical with the other.
Which is more common, "nm" or "nop"?
"nm" is the more common of the two: it sits at frequency rank #22,954 in our French list, against #49,823 for "nop". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

Useful next steps

Pair "nm" vs "nop" is on the table, pick a follow-up below.

  • Full dictionary entry for "nm" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "nop" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #42,799 of 440,172 scored French confusable pairs in this corpus vintage. Corpus statistics
  • "nm" and "nop" also get mixed up with nearby pairs, the highest-scored neighbour is "nis vs nop". Nearby pair

Confusion rank #42,799 of 440,172 scored French pairs, corpus vintage 2026-09-03, not spelling advice.

Source: Wiktionary (via kaikki.org) Structured Wiktionary extract

Source: FrequencyWords open word-frequency list