sub

/sʌb/

//sʌb// noun

By · According to Wiktionary data (CC BY-SA) ·

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

The verdict

“sub” is a regularly-used English word, ranked #2,236 in English word frequency and used as a noun.

#2,236
frequency rank, English
3
letters
20
confusable pairs

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - Abbreviation of submarine.

Visual similarity to commonly confused words

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

sub vs SW
0% similar
sub vs SV
0% similar
sub vs Sy
0% similar

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

Key facts for sub
PropertyValue
Headwordsub
LanguageEnglish
Part of speechNoun
IPA/sʌb/
Letters3
Frequency rank#2,236
Misspellings tracked0
Confusable pairs20
SourceWiktionary (kaikki.org)

Where “sub” sits in English frequency

Every-word frequency runs from the handful of words we use constantly (left) to the long tail used once in a blue moon (right). sub lands here:

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

Scale is logarithmic (each tick is 10× rarer). Source: FrequencyWords open word-frequency list.

Spelling & Dictionary Insight

The English entry for sub is 3 letters long, classified as a noun, and transcribed in the International Phonetic Alphabet as /sʌb/. Corpus data places it at rank #2,236 in overall English word frequency, indicating it appears regularly in written and spoken text. Wiktionary records 19 distinct senses for this headword, so context determines which meaning a reader should apply.

Zero misspellings are on record for sub in our index, a straightforward case of a spelling with little room for common typos. It also participates in 20 confusable-pair relationships, "SW", "SV", "Sy", and more, where similar look or sound leads writers to substitute one word for another in context.

Etymologically, the entry records: * Shortened form of any of various words beginning with sub-. The correct English form is sub, spelled S-U-B.

Definition

  1. 1
    Abbreviation of submarine.
  2. 2
    Clipping of submarine sandwich: a sandwich made on a long bun.
  3. 3
    Clipping of submersible.
  4. 4
    Clipping of substitute, often in sports or teaching.
  5. 5
    Clipping of subscription (“a payment made for membership of a club, etc.”).
  6. 6
    Clipping of subtitle
  7. 7
    Clipping of subroutine (sometimes one that does not return a value, as distinguished from a function, which does)
  8. 8
    Clipping of subeditor
  9. 9
    Clipping of subcontractor
  10. 10
    Clipping of subwoofer
  11. 11
    Clipping of submission (of a work for publication).
  12. 12
    Clipping of submissive
  13. 13
    Clipping of subordinate
  14. 14
    Clipping of subaltern
  15. 15
    Clipping of subscription (or (by extension) a subscriber) to an online channel or feed.
  16. 16
    Clipping of subsistence money, part of a worker's wages paid before the work is finished.
  17. 17
    Clipping of subreddit.
  18. 18
    Clipping of subject (“particular area of study”)
  19. 19
    Clipping of subliminal (“an audio or video recording intended to produce physical or psychological changes in the listener”)

Etymology

* Shortened form of any of various words beginning with sub-.

This word in other languages

submarino(Español)U-Boot(Deutsch)

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 "sub"?
"sub" is spelled S-U-B. The IPA pronunciation is /sʌb/.
What does "sub" mean?
As a noun, "sub" means: Abbreviation of submarine.
What words are commonly confused with "sub"?
"sub" is commonly confused with "SW", "SV", "Sy". These words look or sound similar but have different meanings. PlainSpell provides detailed comparisons for each pair.
How do you pronounce "sub"?
The IPA (International Phonetic Alphabet) transcription for "sub" is /sʌb/. Click the speaker icon on the pronunciation badge above to hear it spoken aloud where audio is available.
What is the origin of the word "sub"?
* Shortened form of any of various words beginning with sub-. See the full etymology section above for more details.
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.

Using “sub”

The practical upshot for anyone who landed here from a spell-check.

  • The one correct English spelling is S-U-B - every other letter order is a misspelling in standard orthography.
  • Say it as /sʌb/ (IPA); tap the speaker on the pronunciation badge to hear it where audio exists.
  • Don't mix it up with “SW” - see the side-by-side comparison. sub vs SW
  • Browse more English words and confusable pairs in the same reference. English words
Data Source

Wiktionary (via kaikki.org), licensed under CC BY-SA & GFDL. Word ordering uses an open word-frequency list; misspelling variants are generated by edit-distance from the correct headword.

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

Source: FrequencyWords open word-frequency list FrequencyWords open word-frequency list