RSV

noun

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

The verdict

“RSV” is uncommon English (frequency #51,374 among 3,094 “R” headwords), classed as a noun. The kind of spelling people second-guess.

#51,374
frequency rank, English
3,094
“R” headwords

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - Initialism of respiratory syncytial virus.

Corpus desk

Index EN-rsv · RSV · English

RSV · rank #51,374 · 0 variants · 0 confusables

  • FREQ-RARE #51,374
  • LEN-MID 3 letters
  • VOW-0 0 vowels
  • CONFUS-0 No pairs
  • VAR-0 0 variants
  • BOOK-MID 3,094
  • PHOTO-FINISH rosin

Nearest frequency peer: rosin (-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.

Long-tail ranks near “RSV”

Sparse band: bars invert rank so rarer forms read shorter

corpus weight

What this shows Long-tail view: where “RSV” sits against similarly uncommon English ranks.

Source FrequencyWords open word-frequency list As of September 3, 2026
Key facts for RSV
PropertyValue
HeadwordRSV
LanguageEnglish
Part of speechNoun
Letters3
Frequency rank#51,374
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Long-tail rank of “RSV” in English

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

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

Ticks step logarithmically, so each one marks a roughly tenfold drop in how often the word turns up. Rare peers in the same band: “rosin” (#51,373), “rubella” (#51,375), “Robeson” (#51,370). Among 3,094 “R” headwords, “RSV” is #51,374. Source: FrequencyWords open word-frequency list.

Rare enough to double-check

RSV is uncommon English at frequency #51,374 among 3,094 “R” headwords, classed as anoun. Rarity is why readers land here mid-draft. 2 senses are on record.

No misspelling variants are generated for RSV in our index, which points to an orthography that plays by predictable English rules. We don't track a confusable pairing for this entry, since nothing in our dataset looks or sounds close enough to cause mix-ups.

Wiktionary doesn't record an etymology for this headword, so its spelling pattern is best understood through pronunciation rather than a traceable origin. The correct English form is RSV, spelled R-S-V.

Definition

  1. 1
    Initialism of respiratory syncytial virus.
  2. 2
    Initialism of research survey vessel.

Recorded use

Wiktionary examples

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

  1. While most children will get RSV by age 2, getting sick is never ideal and for young children, or those at high risk for severe RSV disease.
  2. The spokesperson said other science climate science projects would be restored, with four extra scientists approved to travel south on the icebreaking research vessel RSV Nuyina.

This word in other languages

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 "RSV"?
"RSV" is spelled R-S-V.
What does "RSV" mean?
As a noun, "RSV" means: Initialism of respiratory syncytial virus.
What language does "RSV" come from?
"RSV" 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 "RSV", 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