uracil

/ˈjʊərəsɪl/

//ˈjʊərəsɪl// noun

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

"uracil" is a 6-letter English headword indexed on PlainSpell.

The verdict

“uracil” is uncommon English (frequency #98,850 among 1,433 “U” headwords), classed as a noun. The kind of spelling people second-guess.

#98,850
frequency rank, English
1,433
“U” headwords

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - One of the bases of RNA, pairing with adenine.

Corpus desk

Index EN-uracil · uracil · English

uracil · rank #98,850 · 0 variants · 0 confusables

  • FREQ-RARE #98,850
  • LEN-LONG 6 letters
  • VOW-3 3 vowels
  • CONFUS-0 No pairs
  • VAR-0 0 variants
  • BOOK-MID 1,433
  • PHOTO-FINISH upgradeable

Nearest frequency peer: upgradeable (-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 neighbourhood for “uracil”

Lower corpus rank = more everyday usage (inverted bar length for readability)

corpus weight

What this shows Bars show where “uracil” sits against the nearest ranked English headwords in the FrequencyWords band, not a reprint of letter-browse containment.

Source FrequencyWords open word-frequency list As of September 3, 2026
Key facts for uracil
PropertyValue
Headworduracil
LanguageEnglish
Part of speechNoun
IPA/ˈjʊərəsɪl/
Letters6
Frequency rank#98,850
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Where “uracil” 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). uracil lands here:

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

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

Rare enough to double-check

uracil is uncommon English at frequency #98,850 among 1,433 “U” headwords, classed as anoun, transcribed /ˈjʊərəsɪl/. Rarity is why readers land here mid-draft. Gloss: "One of the bases of RNA, pairing with adenine.".

No generated misspelling entries exist for uracil in our index, a straightforward case of a spelling with little room for common typos. No confusable counterpart is on file for this word, which usually means its spelling is distinct enough that readers don't reach for a similar-looking word instead.

Etymologically, the entry records: From uro- + ac(etic) + -ile. Coined in 1885 by the German chemist Robert Behrend, who was attempting to synthesize derivatives of uric acid. The correct English form is uracil, spelled U-R-A-C-I-L.

Definition

  1. 1
    One of the bases of RNA, pairing with adenine.

Recorded use

Wiktionary example

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

  1. We did have some success with uracil when we would preincorporate the uracil into a mutant of E. coli that had a uracil requirement and then feed this cellular content from E. coli.

Etymology

From uro- + ac(etic) + -ile. Coined in 1885 by the German chemist Robert Behrend, who was attempting to synthesize derivatives of uric acid.

This word in other languages

uracilo(Español)uracile(Français)Uracil(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.

PlainSpell is rendered directly from structured Wiktionary extracts and open word-frequency lists, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of September 3, 2026. Primary sources: Wiktionary (via kaikki.org) and FrequencyWords.

Frequently Asked Questions

How do you spell "uracil"?
"uracil" is spelled U-R-A-C-I-L. The IPA pronunciation is /ˈjʊərəsɪl/.
What does "uracil" mean?
As a noun, "uracil" means: One of the bases of RNA, pairing with adenine.
How do you pronounce "uracil"?
The IPA (International Phonetic Alphabet) transcription for "uracil" is /ˈjʊərəsɪl/. 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 "uracil"?
From uro- + ac(etic) + -ile. Coined in 1885 by the German chemist Robert Behrend, who was attempting to synthesize derivatives of uric acid. 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.

Similar English words by spelling shape

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

Same letter count

Frequency-ranked English headwords with 6 letters (nearest by frequency rank).

Ugarte#98,837twitty#98,835troppo#98,823WebApp#98,881

What to do next

You've looked up "uracil". Here's where to go from here.

  • Usage frequency rank #98,850 among English headwords in this corpus. Corpus statistics
  • Browse more English words in the "U" letter cohort. U–Z browse
  • PlainSpell rotates a curated Word of the Day from the English corpus, a passive way to discover vocabulary. Word of the Day

PlainSpell is a reference corpus, not spelling advice. Verify unusual forms in context.

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