threonine
"threonine" is a 9-letter English headword indexed on PlainSpell.
The verdict
“threonine” is uncommon English (frequency #69,511 among 27,828 “T” headwords), classed as a noun. The kind of spelling people second-guess.
- #69,511
- frequency rank, English
- 27,828
- “T” headwords
According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - An essential amino acid C₄H₉NO₃ found in most animal proteins.
| Property | Value |
|---|---|
| Headword | threonine |
| Language | English |
| Part of speech | Noun |
| Letters | 9 |
| Frequency rank | #69,511 |
| Misspellings tracked | 0 |
| Confusable pairs | 0 |
| Source | Wiktionary (kaikki.org) |
Where “threonine” sits in English frequency
Rare enough to double-check
threonine is uncommon English at frequency #69,511 among 27,828 “T” headwords, classed as anoun. Rarity is why readers land here mid-draft. Gloss: "An essential amino acid C₄H₉NO₃ found in most animal proteins.".
No misspelling variants are generated for threonine in our index, and the word's spelling is regular enough that our generator found nothing worth flagging. This entry stands alone in our confusable dataset, since its spelling is unusual enough that it doesn't cluster with a lookalike.
Etymologically, the entry records: From threose. The correct English form is threonine, spelled T-H-R-E-O-N-I-N-E.
Definition
- 1An essential amino acid C₄H₉NO₃ found in most animal proteins.
Etymology
From threose.
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
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Using “threonine”
The practical upshot for anyone who landed here from a spell-check.
- The one correct English spelling is T-H-R-E-O-N-I-N-E - every other letter order is a misspelling in standard orthography.
- 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.