nigh vs NIH, What's the Difference?

Which to use

“nigh” is an adjective and “NIH” is a name - they look or sound alike but fill different roles in a sentence.

#21,298
“nigh” frequency rank: #18,376
“NIH” frequency rank: 39674
confusion score

Side-by-Side Comparison

Feature	nigh	NIH
Definition	Near, close by.	Initialism of National Institutes of Health.

Letter map: nigh vs NIH

Shared letters muted; letters that set nigh and NIH apart highlighted. Shared run: 3.

4 ch

nigh

3 ch

NIH

Grammar separator: nigh vs NIH

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: nigh is anadjective and NIHaname. On the page they differ by 1 letter(s) in length. Our composite confusion score for this pair is 39674, derived from the frequency rank of both members and their visual similarity.

nigh is recorded at frequency rank #21,298, classified as anadj, pronounced /naɪ/. NIH is at rank #18,376, 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 39674, this pair ranks #274,553 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of nigh vs NIH

Shared letters: hin. Private to "nigh": g. Private to "NIH": -.

"nigh" · 4 letters · shape CVCC · "NIH" · 3 letters · shape CVC

Known mistypes of this pair

nigh ← ingh · ngih · niggh · nighh · nihg · nnigh

Frequently Asked Questions

Do "nigh" and "NIH" mean the same thing in a sentence?

No - they are not even the same part of speech. "nigh" is an adjective and "NIH" a name, so a sentence built for one is usually ungrammatical with the other.

Frequency check: "nigh" vs "NIH" - which ranks higher?

"NIH" is the more common of the two: it sits at frequency rank #18,376 in our English list, against #21,298 for "nigh". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

What to do next

Done with this confusable. These links stay specific to "nigh" and "NIH".

Full dictionary entry for "nigh" with definition, IPA, and generated misspellings. Word entry
Full dictionary entry for "NIH" - compare definitions side by side with the headword page. Word entry
This pair ranks #274,553 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
"nigh" and "NIH" also get mixed up with nearby pairs, the highest-scored neighbour is "NEH vs nigh". Nearby pair
Recorded mistypes exist for at least one side of this pair, useful when a spell-checker or OCR lands on the wrong form. See mistypes

Confusion rank #274,553 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.