sildenafil
/sɪlˈdɛn.ə.fɪl/
"sildenafil" is a 10-letter English headword indexed on PlainSpell.
The verdict
“sildenafil” is uncommon English (frequency #87,827 among 54,294 “S” headwords), classed as a noun. The kind of spelling people second-guess.
- #87,827
- frequency rank, English
- 54,294
- “S” headwords
According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - A drug that is used in the form of its citrate C₂₂H₃₀N₆O₄S·C₆H₈O₇ to treat erectile dysfunction in males, that by suppressing a phosphodiesterase enzyme also suppresses the enzyme's inhibitory effe...
Corpus desk
Index EN-sildenafil · sildenafil · English
sildenafil · rank #87,827 · 0 variants · 0 confusables
- FREQ-RARE #87,827
- LEN-MEGA 10 letters
- VOW-4 4 vowels
- CONFUS-0 No pairs
- VAR-0 0 variants
- BOOK-DENSE 54,294
- PHOTO-FINISH silverfish
Nearest frequency peer: silverfish (+2 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 “sildenafil”
Lower corpus rank = more everyday usage (inverted bar length for readability)
- shola
shola
12,182 corpus weight
- sildenafil
sildenafil
12,174 corpus weight
- silverfish
silverfish
12,172 corpus weight
- sinewy
sinewy
12,171 corpus weight
- Singhal
Singhal
12,170 corpus weight
- Skeffington
Skeffington
12,167 corpus weight
What this shows Bars show where “sildenafil” sits against the nearest ranked English headwords in the FrequencyWords band, not a reprint of letter-browse containment.
| Property | Value |
|---|---|
| Headword | sildenafil |
| Language | English |
| Part of speech | Noun |
| IPA | /sɪlˈdɛn.ə.fɪl/ |
| Letters | 10 |
| Frequency rank | #87,827 |
| Misspellings tracked | 0 |
| Confusable pairs | 0 |
| Source | Wiktionary (kaikki.org) |
Where “sildenafil” sits in English frequency
Rare enough to double-check
sildenafil is uncommon English at frequency #87,827 among 54,294 “S” headwords, classed as anoun, transcribed /sɪlˈdɛn.ə.fɪl/. Rarity is why readers land here mid-draft. Gloss: "A drug that is used in the form of its citrate C₂₂H₃₀N₆O₄S·C₆H₈O₇ to treat erectile dysfunction in males, that by suppressing a phosphodiesterase enzyme also suppresses the enzyme's inhibitory effe...".
No misspelling variants are generated for sildenafil in our index, a straightforward case of a spelling with little room for common typos. We don't track a confusable pairing for this entry, since its spelling is unusual enough that it doesn't cluster with a lookalike.
Etymologically, the entry records: Probably from s(ulfon)yl + -dena- (“alteration of (pyrimi)dine”) + ph(en)yl. The correct English form is sildenafil, spelled S-I-L-D-E-N-A-F-I-L.
Definition
- 1A drug that is used in the form of its citrate C₂₂H₃₀N₆O₄S·C₆H₈O₇ to treat erectile dysfunction in males, that by suppressing a phosphodiesterase enzyme also suppresses the enzyme's inhibitory effect on the hormone cyclic GMP, and that enables the cyclic GMP produced during sexual arousal to initiate the muscular and vascular changes which produce an erection. It is marketed under the trademarks Revatio and Viagra.
Etymology
Probably from s(ulfon)yl + -dena- (“alteration of (pyrimi)dine”) + ph(en)yl.
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 May 6, 2026. Primary sources: Wiktionary (via kaikki.org) and FrequencyWords.
Frequently Asked Questions
How do you spell "sildenafil"?
What does "sildenafil" mean?
How do you pronounce "sildenafil"?
What is the origin of the word "sildenafil"?
Is PlainSpell free to use?
Similar English words by spelling shape
Same letter count and similar misspelling depth for "sildenafil", not the corpus desk frequency band.
Same letter count
Frequency-ranked English headwords with 10 letters (nearest by frequency 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.