NSF

name

"nsf" is a 3-letter English headword indexed on PlainSpell.

The verdict

“NSF” sits in 20 confusable pairs (corpus #27,233) as a proper noun. The look-alike neighbours are the real trap.

#27,233
frequency rank, English
1,534
“N” headwords
20
confusable pairs

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - Initialism of National Science Foundation.

Corpus desk

Index EN-nsf · NSF · English

NSF · rank #27,233 · 0 variants · 20 confusables

  • FREQ-MID #27,233
  • LEN-MID 3 letters
  • VOW-0 0 vowels
  • CONFUS-HIGH 20 pairs
  • VAR-0 0 variants
  • BOOK-MID 1,534
  • PHOTO-FINISH observant

Nearest frequency peer: observant (+1 rank slots)

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.

Frequency neighbours of confusable “NSF”

Peers at similar corpus weight, separate from look-alike pairs below

corpus weight

What this shows Bars place “NSF” against nearest ranked English headwords, not a reprint of the confusable-pair desk.

Source FrequencyWords open word-frequency list As of September 3, 2026

Visual similarity to commonly confused words

How many letter changes separate each confused pair (Levenshtein distance, normalized).

NSF vs NZ
33% similar
NSF vs NT
33% similar
NSF vs nu
0% similar

Source: PlainSpell confusable corpus (Wiktionary, CC BY-SA).

Key facts for NSF
PropertyValue
HeadwordNSF
LanguageEnglish
Part of speechProper noun
Letters3
Frequency rank#27,233
Misspellings tracked0
Confusable pairs20
SourceWiktionary (kaikki.org)

Corpus rank beside confusables of “NSF”

This scale runs from the tiny cluster of words that carry ordinary speech (left) to the long tail of words almost nobody reaches for (right).NSFlands here:

#1#100#1K#10K#100K
← used constantlyrarely used →

The axis is logarithmic, with each marked tick roughly ten times rarer than the last. Same rarity band neighbours include “observant” (#27,234), “Navarro” (#27,230), “ostrich” (#27,236). Among 1,534 “N” headwords, “NSF” is #27,233. Source: FrequencyWords open word-frequency list.

Easy to mix with look-alikes

The spelling risk for NSF is neighbouring look-alikes ("NZ", "NT", …), not just typos; it is aproper noun. Frequency #27,233 among 1,534 “N” headwords. Gloss: "Initialism of National Science Foundation.".

NSF has no tracked misspelling variants, a sign its spelling follows regular English conventions. It also participates in 20 confusable-pair relationships, "NZ", "NT", "nu", and more, where similar look or sound leads writers to substitute one word for another in context.

This entry's etymology isn't recorded, so any spelling logic here comes from how the word's sounds map to letters, not a documented origin story. The correct English form is NSF, spelled N-S-F.

Definition

  1. 1
    Initialism of National Science Foundation.

Recorded use

Wiktionary example

These source excerpts show how NSF appears in context. They illustrate usage; the definition above remains the entry’s reference meaning.

  1. Those overall numbers are in line with Schumer's year-old plan to make NSF the spearpoint of a massive federal investment in research aimed at outinnovating China.

Definitions, pronunciation, and etymology for this entry are drawn from Wiktionary via the kaikki.org structured extract (CC BY-SA); frequency ordering uses the FrequencyWords open word-frequency list (2018 English corpus, MIT). See the methodology for how each field is sourced and updated.

Frequently Asked Questions

How do you spell "NSF"?
"NSF" is spelled N-S-F.
What does "NSF" mean?
As a proper noun, "NSF" means: Initialism of National Science Foundation.
What words are commonly confused with "NSF"?
"NSF" is commonly confused with "NZ", "NT", "nu". These words look or sound similar but have different meanings. PlainSpell provides detailed comparisons for each pair.
What language does "NSF" come from?
"NSF" is a English word. You can look up definitions, pronunciations, and spelling data for this and other words across English, Spanish, Portuguese, French, and German on PlainSpell.
Is PlainSpell free to use?
Yes, PlainSpell is a completely free word reference. You can look up definitions, pronunciations, confusable pairs, homophones, and spelling corrections across 5 languages without any sign-up or subscription.

Similar English words by spelling shape

Same letter count and similar misspelling depth for "NSF", not the corpus desk frequency band.

Same letter count

Frequency-ranked English headwords with 3 letters (nearest by frequency rank).

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

Source: FrequencyWords open word-frequency list