diphenhydramine
/ˌdʌɪ.fɛnˈhʌɪ.dɹəm.iːn/
"diphenhydramine" is a 15-letter English headword indexed on PlainSpell.
The verdict
“diphenhydramine” is uncommon English (frequency #88,276 among 26,416 “D” headwords), classed as a noun. The kind of spelling people second-guess.
- #88,276
- frequency rank, English
- 26,416
- “D” headwords
According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - An antihistamine and anticholinergic drug that blocks the effect of histamine at H₁ receptor sites, relieving allergy symptoms. It also reduces smooth muscle contraction, increases heart rate, and ...
| Property | Value |
|---|---|
| Headword | diphenhydramine |
| Language | English |
| Part of speech | Noun |
| IPA | /ˌdʌɪ.fɛnˈhʌɪ.dɹəm.iːn/ |
| Letters | 15 |
| Frequency rank | #88,276 |
| Misspellings tracked | 0 |
| Confusable pairs | 0 |
| Source | Wiktionary (kaikki.org) |
Where “diphenhydramine” sits in English frequency
Rare enough to double-check
diphenhydramine is uncommon English at frequency #88,276 among 26,416 “D” headwords, classed as anoun, transcribed /ˌdʌɪ.fɛnˈhʌɪ.dɹəm.iːn/. Rarity is why readers land here mid-draft. Gloss: "An antihistamine and anticholinergic drug that blocks the effect of histamine at H₁ receptor sites, relieving allergy symptoms. It also reduces smooth muscle contraction, increases heart rate, and ...".
We couldn't generate a plausible misspelling set for diphenhydramine, since its letter pattern doesn't lend itself to common typo substitutions. This entry stands alone in our confusable dataset, which typically means the spelling is too distinctive to be mistaken for another word.
Etymologically, the entry records: From diphen(yl) + (benz)hydr(yl) + -amine. The correct English form is diphenhydramine, spelled D-I-P-H-E-N-H-Y-D-R-A-M-I-N-E.
Definition
- 1An antihistamine and anticholinergic drug that blocks the effect of histamine at H₁ receptor sites, relieving allergy symptoms. It also reduces smooth muscle contraction, increases heart rate, and sedates the user by blocking muscarinic acetylcholine receptors (mAChRs).
Etymology
From diphen(yl) + (benz)hydr(yl) + -amine.
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 "diphenhydramine"?
What does "diphenhydramine" mean?
How do you pronounce "diphenhydramine"?
What is the origin of the word "diphenhydramine"?
Is PlainSpell free to use?
Using “diphenhydramine”
The practical upshot for anyone who landed here from a spell-check.
- The one correct English spelling is D-I-P-H-E-N-H-Y-D-R-A-M-I-N-E - every other letter order is a misspelling in standard orthography.
- Say it as /ˌdʌɪ.fɛnˈhʌɪ.dɹəm.iːn/ (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.