penicillin

/ˌpɛn.ɪˈsɪl.ɪn/

//ˌpɛn.ɪˈsɪl.ɪn// noun

By · According to Wiktionary data (CC BY-SA) ·

"penicillin" is a 10-letter English headword indexed on PlainSpell.

The verdict

“penicillin” has 13 generated spelling variants in the English index at frequency #27,594. The variants make it a useful spelling check.

#27,594
frequency rank, English
4,417
“P” headwords
13
tracked misspellings

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - Any of a group of narrow-spectrum antibiotics obtained from Penicillium molds or synthesized, that have a beta-lactam structure and are active against gram-positive bacteria and used in the treatme...

Corpus desk

Index EN-penicillin · penicillin · English

penicillin · rank #27,594 · 13 variants · 0 confusables

  • FREQ-MID #27,594
  • LEN-MEGA 10 letters
  • VOW-4 4 vowels
  • CONFUS-0 No pairs
  • VAR-HIGH 13 variants
  • BOOK-MID 4,417
  • PHOTO-FINISH pausing

Nearest frequency peer: pausing (-1 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.

Rank peers near misspelling magnet “penicillin”

Same rarity band: useful when a typo lands on a peer headword

corpus weight

What this shows “penicillin” sits among these FrequencyWords peers; misspelling depth is tracked separately in the edit-distance chart.

Source FrequencyWords open word-frequency list As of September 3, 2026
Key facts for penicillin
PropertyValue
Headwordpenicillin
LanguageEnglish
Part of speechNoun
IPA/ˌpɛn.ɪˈsɪl.ɪn/
Letters10
Frequency rank#27,594
Misspellings tracked13
Confusable pairs0
SourceWiktionary (kaikki.org)

Frequency seat of misspelling magnet “penicillin”

Word frequency stretches from the small set of words we reach for constantly (left) out to the long tail barely used once in a while (right).penicillinlands here:

#1#100#1K#10K#100K
← used constantlyrarely used →

Ticks step logarithmically, so each one marks a roughly tenfold drop in how often the word turns up. Same rarity band neighbours include “pausing” (#27,593), “perfecting” (#27,595), “particulate” (#27,592). Among 4,417 “P” headwords, “penicillin” is #27,594. Source: FrequencyWords open word-frequency list.

A misspelling magnet

The generator records 13 spelling variants around penicillin (IPA /ˌpɛn.ɪˈsɪl.ɪn/), anoun. Corpus frequency is #27,594 among 4,417 “P” headwords. Wiktionary lists 2 senses, so context still picks the gloss.

Our generated misspelling index lists 13 likely wrong-spelling variants for penicillin, with forms such as "epnicillin", "peincillin", and "penciillin". Each of these forms differs from the correct spelling by one small edit: a doubled letter, a dropped silent letter, or a substituted vowel. Our dataset records no confusable match here, a sign it's visually distinctive enough not to be mixed up with another word.

Etymologically, the entry records: From translingual Penicillium + -in. Coined by Alexander Fleming after Penicillium notatum (now Penicillium chrysogenum), a fungus from which penicillin is obtained. The correct English form is penicillin, spelled P-E-N-I-C-I-L-L-I-N.

Definition

  1. 1
    Any of a group of narrow-spectrum antibiotics obtained from Penicillium molds or synthesized, that have a beta-lactam structure and are active against gram-positive bacteria and used in the treatment of various infections and diseases.
  2. 2
    A blue mold of the genus Penicillium that produces penicillin.

Etymology

From translingual Penicillium + -in. Coined by Alexander Fleming after Penicillium notatum (now Penicillium chrysogenum), a fungus from which penicillin is obtained.

This word in other languages

penicilina(Español)pénicilline(Français)Penicillin(Deutsch)penicilina(Português)

Common misspellings

Also misspelled as:

  • epnicillin
  • peincillin
  • penciillin
  • peniccillin
  • penicililn
  • penicilin
  • penicillinn
  • penicillni
  • peniclilin
  • peniicllin
  • pennicillin
  • pneicillin
  • ppenicillin

Misspelling Pattern Breakdown

How far each generated variant is from the correct spelling of penicillin - measured in single-character edits (insert, delete, or substitute a letter). Larger bars are easier to catch; one-edit slips are the sneakiest.

epnicillin2peincillin2penciillin2peniccillin1penicililn2penicilin1penicillinn1penicillni2
Edit distance from "penicillin"

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 "penicillin"?
"penicillin" is spelled P-E-N-I-C-I-L-L-I-N. The IPA pronunciation is /ˌpɛn.ɪˈsɪl.ɪn/.
What does "penicillin" mean?
As a noun, "penicillin" means: Any of a group of narrow-spectrum antibiotics obtained from Penicillium molds or synthesized, that have a beta-lactam structure and are active against gram-positive bacteria and used in the treatme...
What are common misspellings of "penicillin"?
Common misspellings include "epnicillin", "peincillin", "penciillin", "peniccillin", "penicililn". The correct spelling is "penicillin".
How do you pronounce "penicillin"?
The IPA (International Phonetic Alphabet) transcription for "penicillin" is /ˌpɛn.ɪˈsɪl.ɪn/. Click the speaker icon on the pronunciation badge above to hear it spoken aloud where audio is available.
What is the origin of the word "penicillin"?
From translingual Penicillium + -in. Coined by Alexander Fleming after Penicillium notatum (now Penicillium chrysogenum), a fungus from which penicillin is obtained. See the full etymology section above for more details.
Is PlainSpell free to use?
Yes, PlainSpell is a completely free word reference. You can look up definitions, pronunciations, confusable pairs, homophones, and spelling corrections across 5 languages without any sign-up or subscription.

Similar English words by spelling shape

Same letter count and similar misspelling depth for "penicillin", not the corpus desk frequency band.

Same letter count

Frequency-ranked English headwords with 10 letters (nearest by frequency rank).

perfecting#27,595obstetrics#27,586monochrome#27,568rheumatoid#27,623

Similar misspelling depth

Headwords with a similar count of attested misspellings (13 here; floor ≥5).

Provence13 variantssanctity13 variantsMcGovern13 variantsstalemate13 variants

Source: Wiktionary (via kaikki.org) Structured Wiktionary extract

Source: FrequencyWords open word-frequency list