NCO

noun

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

The verdict

“NCO” sits in 20 confusable pairs (corpus #44,957) as a noun. The look-alike neighbours are the real trap.

#44,957
frequency rank, English
1,534
“N” headwords
20
confusable pairs

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - Initialism of numerically controlled oscillator.

Corpus desk

Index EN-nco · NCO · English

NCO · rank #44,957 · 0 variants · 20 confusables

  • FREQ-MID #44,957
  • LEN-MID 3 letters
  • VOW-1 1 vowel
  • CONFUS-HIGH 20 pairs
  • VAR-0 0 variants
  • BOOK-MID 1,534
  • PHOTO-FINISH Nehemiah

Nearest frequency peer: Nehemiah (+2 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 “NCO”

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

corpus weight

What this shows Bars place “NCO” 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).

NCO vs ne
0% similar
NCO vs NJ
33% similar
NCO vs ni
0% similar

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

Key facts for NCO
PropertyValue
HeadwordNCO
LanguageEnglish
Part of speechNoun
Letters3
Frequency rank#44,957
Misspellings tracked0
Confusable pairs20
SourceWiktionary (kaikki.org)

Corpus rank beside confusables of “NCO”

Word frequency stretches from the small set of words we reach for constantly (left) out to the long tail barely used once in a while (right).NCOlands 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 “Nehemiah” (#44,959), “natively” (#44,954), “nape” (#44,953). Among 1,534 “N” headwords, “NCO” is #44,957. Source: FrequencyWords open word-frequency list.

Easy to mix with look-alikes

The spelling risk for NCO is neighbouring look-alikes ("ne", "NJ", …), not just typos; it is anoun. Frequency #44,957 among 1,534 “N” headwords. 2 recorded senses keep meaning in play.

We couldn't generate a plausible misspelling set for NCO, a sign its spelling follows regular English conventions. It also participates in 20 confusable-pair relationships, "ne", "NJ", "ni", and more, since the words sound or look close enough that writers reach for the wrong one mid-sentence.

This headword's origin isn't recorded in our source data, so its spelling is easiest to reason about phoneme by phoneme, absent a documented history. The correct English form is NCO, spelled N-C-O.

Definition

  1. 1
    Initialism of numerically controlled oscillator.
  2. 2
    Initialism of non-commissioned officer.

Recorded use

Wiktionary examples

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

  1. There was for some reason a shortage not only of regular private soldiers but of officers and NCOs.
  2. For Sgt Kudrya, an NCO who has found himself commanding a company because of a lack of officers, this low-level war means a constant struggle with the elements, paper work (he is under constant pressure from above to account for each litre of petrol and round of ammunition), and the erosion of discipline born of boredom.

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 "NCO"?
"NCO" is spelled N-C-O.
What does "NCO" mean?
As a noun, "NCO" means: Initialism of numerically controlled oscillator.
What words are commonly confused with "NCO"?
"NCO" is commonly confused with "ne", "NJ", "ni". These words look or sound similar but have different meanings. PlainSpell provides detailed comparisons for each pair.
What language does "NCO" come from?
"NCO" is a English word. PlainSpell's reference spans five languages -- English, Spanish, Portuguese, French, and German -- with definitions, pronunciations, and spelling data for each.
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 "NCO", 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