endorphin
/ɛnˈdɔːfɪn/
"endorphin" is a 9-letter English headword indexed on PlainSpell.
The verdict
“endorphin” is uncommon English (frequency #70,637 among 18,836 “E” headwords), classed as a noun. The kind of spelling people second-guess.
- #70,637
- frequency rank, English
- 18,836
- “E” headwords
According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - Any of a group of peptide hormones found in the mammalian brain that act as neurotransmitters and have properties similar to morphine.
| Property | Value |
|---|---|
| Headword | endorphin |
| Language | English |
| Part of speech | Noun |
| IPA | /ɛnˈdɔːfɪn/ |
| Letters | 9 |
| Frequency rank | #70,637 |
| Misspellings tracked | 0 |
| Confusable pairs | 0 |
| Source | Wiktionary (kaikki.org) |
Where “endorphin” sits in English frequency
Rare enough to double-check
endorphin is uncommon English at frequency #70,637 among 18,836 “E” headwords, classed as anoun, transcribed /ɛnˈdɔːfɪn/. Rarity is why readers land here mid-draft. Gloss: "Any of a group of peptide hormones found in the mammalian brain that act as neurotransmitters and have properties similar to morphine.".
endorphin doesn't appear in our generated misspelling index, a sign its spelling follows regular English conventions. No close-neighbour confusable shows up for this headword in our dataset, a sign it's visually distinctive enough not to be mixed up with another word.
Etymologically, the entry records: Borrowed from French endorphine, from endo(gène) (“endogenous, produced within”) and morphine. The correct English form is endorphin, spelled E-N-D-O-R-P-H-I-N.
Definition
- 1Any of a group of peptide hormones found in the mammalian brain that act as neurotransmitters and have properties similar to morphine.
Etymology
Borrowed from French endorphine, from endo(gène) (“endogenous, produced within”) and morphine.
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 "endorphin"?
What does "endorphin" mean?
How do you pronounce "endorphin"?
What is the origin of the word "endorphin"?
Is PlainSpell free to use?
Using “endorphin”
The practical upshot for anyone who landed here from a spell-check.
- The one correct English spelling is E-N-D-O-R-P-H-I-N - every other letter order is a misspelling in standard orthography.
- Say it as /ɛnˈdɔːfɪn/ (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.