leucine
/ˈluː.siːn/
"leucine" is a 7-letter English headword indexed on PlainSpell.
The verdict
“leucine” is uncommon English (frequency #57,517 among 16,425 “L” headwords), classed as a noun. The kind of spelling people second-guess.
- #57,517
- frequency rank, English
- 16,425
- “L” headwords
According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - An essential amino acid, C₆H₁₃NO₂, isomeric with isoleucine, found in most animal proteins; it is essential for growth in children.
| Property | Value |
|---|---|
| Headword | leucine |
| Language | English |
| Part of speech | Noun |
| IPA | /ˈluː.siːn/ |
| Letters | 7 |
| Frequency rank | #57,517 |
| Misspellings tracked | 0 |
| Confusable pairs | 0 |
| Source | Wiktionary (kaikki.org) |
Where “leucine” sits in English frequency
Rare enough to double-check
leucine is uncommon English at frequency #57,517 among 16,425 “L” headwords, classed as anoun, transcribed /ˈluː.siːn/. Rarity is why readers land here mid-draft. Gloss: "An essential amino acid, C₆H₁₃NO₂, isomeric with isoleucine, found in most animal proteins; it is essential for growth in children.".
No misspelling variants are generated for leucine in our index, suggesting the orthography follows predictable English patterns. No close-neighbour confusable shows up for this headword in our dataset, suggesting its spelling stands apart enough that readers rarely confuse it with something else.
Etymologically, the entry records: Derived from Ancient Greek λευκός (leukós, “white”) + -ine, equivalent to leuco- + -ine. The correct English form is leucine, spelled L-E-U-C-I-N-E.
Definition
- 1An essential amino acid, C₆H₁₃NO₂, isomeric with isoleucine, found in most animal proteins; it is essential for growth in children.
Etymology
Derived from Ancient Greek λευκός (leukós, “white”) + -ine, equivalent to leuco- + -ine.
Synonyms
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 "leucine"?
What does "leucine" mean?
How do you pronounce "leucine"?
What is the origin of the word "leucine"?
Is PlainSpell free to use?
Using “leucine”
The practical upshot for anyone who landed here from a spell-check.
- The one correct English spelling is L-E-U-C-I-N-E - every other letter order is a misspelling in standard orthography.
- Say it as /ˈluː.siːn/ (IPA); tap the speaker on the pronunciation badge to hear it where audio exists.
- Browse more English words and confusable pairs in the same reference. English words
Other uncommon English words near this rank
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.