USO
"uso" is a 3-letter English headword indexed on PlainSpell.
The verdict
“USO” is a moderately-common English word, ranked #35,573 in English word frequency and used as a noun.
- #35,573
- frequency rank, English
- 3
- letters
- 20
- confusable pairs
According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - Unidentified submerged object or unidentified submarine object.
Visual similarity to commonly confused words
How many letter changes separate each confused pair (Levenshtein distance, normalized).
Source: PlainSpell confusable corpus (Wiktionary, CC BY-SA).
| Property | Value |
|---|---|
| Headword | USO |
| Language | English |
| Part of speech | Noun |
| Letters | 3 |
| Frequency rank | #35,573 |
| Misspellings tracked | 0 |
| Confusable pairs | 20 |
| Source | Wiktionary (kaikki.org) |
Where “USO” sits in English frequency
Spelling & Dictionary Insight
The English entry for USO is 3 letters long, classified as a noun. Corpus data places it at rank #35,573 in overall English word frequency, marking it as uncommon enough that many writers pause before typing it. The dominant gloss from Wiktionary reads: "Unidentified submerged object or unidentified submarine object.".
USO has no tracked misspelling variants, suggesting the orthography follows predictable English patterns. It also participates in 20 confusable-pair relationships, "UT", "UV", "UW", and more, since the words sound or look close enough that writers reach for the wrong one mid-sentence.
Etymologically, the entry records: Initialism. The correct English form is USO, spelled U-S-O.
Definition
- 1Unidentified submerged object or unidentified submarine object.
Etymology
Initialism.
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 "USO"?
What does "USO" mean?
What words are commonly confused with "USO"?
What is the origin of the word "USO"?
Is PlainSpell free to use?
Using “USO”
The practical upshot for anyone who landed here from a spell-check.
- The one correct English spelling is U-S-O - every other letter order is a misspelling in standard orthography.
- Don't mix it up with “UT” - see the side-by-side comparison. USO vs UT
- 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.