nepvsNSFTell them apart

Quick tell: nep is a noun, NSF is a name, so they fill different roles in a sentence.

Which to use

“nep” is a noun and “NSF” is a name - they look or sound alike but fill different roles in a sentence.

#45,538
“nep” frequency rank
#27,233
“NSF” frequency rank
72771
confusion score

Side-by-Side Comparison

Feature nep NSF
Definition Catmint, catnip; Nepeta cataria. Initialism of National Science Foundation.

Letter map: nep vs NSF

Shared letters muted; letters that set nep and NSF apart highlighted. Shared run: 1. nep (CVC) and NSF (CCC) run the same length but a different consonant-vowel pattern - the shape difference is usually the fastest tell.

3 ch
nep
3 ch
NSF

Part-of-speech tell for nep / NSF

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: nep is anoun and NSFaname. On the page they share most of their letters but differ in 2 positions. Our composite confusion score for this pair is 72771, derived from the frequency rank of both members and their visual similarity.

nep is recorded at frequency rank #45,538, classified as anoun, pronounced /nɛp/. NSF is at rank #27,233, tagged as aname.

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 72771, this pair ranks #41,916 of 530,003 scored English confusable pairs - among the most confusable pairs.

Orthographic DNA of nep vs NSF

Shared letters: n. Private to "nep": ep. Private to "NSF": fs.

"nep" · 3 letters · shape CVC  ·  "NSF" · 3 letters · shape CCC

Frequently Asked Questions

Is swapping "nep" for "NSF" ever safe?
No - they are not even the same part of speech. "nep" is a noun and "NSF" a name, so a sentence built for one is usually ungrammatical with the other.
Frequency check: "nep" vs "NSF" - which ranks higher?
"NSF" is the more common of the two: it sits at frequency rank #27,233 in our English list, against #45,538 for "nep". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

Useful next steps

Pair "nep" vs "NSF" is on the table, pick a follow-up below.

  • Full dictionary entry for "nep" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "NSF" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #41,916 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "nep" and "NSF" also get mixed up with nearby pairs, the highest-scored neighbour is "nep vs NPL". Nearby pair

Confusion rank #41,916 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.

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

Source: FrequencyWords open word-frequency list