caffeine

/ˈkæfiːn/

//ˈkæfiːn// noun

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

"caffeine" is a 8-letter English headword indexed on PlainSpell.

The verdict

“caffeine” has 9 generated spelling variants in the English index at frequency #11,661. The variants make it a useful spelling check.

#11,661
frequency rank, English
5,599
“C” headwords
9
tracked misspellings

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - An alkaloid, C₈H₁₀N₄O₂, found naturally in tea and coffee plants, which acts as a mild stimulant on the central nervous system.

Corpus desk

Index EN-caffeine · caffeine · English

caffeine · rank #11,661 · 9 variants · 0 confusables

  • FREQ-MID #11,661
  • LEN-LONG 8 letters
  • VOW-4 4 vowels
  • CONFUS-0 No pairs
  • VAR-MID 9 variants
  • BOOK-DENSE 5,599
  • PHOTO-FINISH bunker

Nearest frequency peer: bunker (-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 “caffeine”

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

corpus weight

What this shows “caffeine” 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 caffeine
PropertyValue
Headwordcaffeine
LanguageEnglish
Part of speechNoun
IPA/ˈkæfiːn/
Letters8
Frequency rank#11,661
Misspellings tracked9
Confusable pairs0
SourceWiktionary (kaikki.org)

Frequency seat of misspelling magnet “caffeine”

Every-word frequency runs from the handful of words we use constantly (left) to the long tail used once in a blue moon (right).caffeinelands here:

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

Scale is logarithmic (each tick is 10× rarer). Same rarity band neighbours include “bunker” (#11,660), “capped” (#11,662), “Carlton” (#11,663). Among 5,599 “C” headwords, “caffeine” is #11,661. Source: FrequencyWords open word-frequency list.

A misspelling magnet

The generator records 9 spelling variants around caffeine (IPA /ˈkæfiːn/), anoun. Corpus frequency is #11,661 among 5,599 “C” headwords. Dominant gloss: "An alkaloid, C₈H₁₀N₄O₂, found naturally in tea and coffee plants, which acts as a mild stimulant on the central nervous system.".

Our generated misspelling index lists 9 likely wrong-spelling variants for caffeine, with forms such as "acffeine", "cafefine", and "cafeine". Every one of these variants traces to a single-character edit -- an added or dropped letter, a swapped consonant, or a vowel swap -- the kind of slip a spell-checker is built to catch. No confusable counterpart is on file for this word, a sign it's visually distinctive enough not to be mixed up with another word.

Etymologically, the entry records: Borrowed from French caféine, from café (“coffee”), or German Caffein, Kaffein (cp. Coffein, Koffein), from Kaffee (“coffee”) (cp. Kaffe, Koffee, Koffe), or Italian caffè (“coffee”) + -ine. The correct English form is caffeine, spelled C-A-F-F-E-I-N-E.

Definition

  1. 1
    An alkaloid, C₈H₁₀N₄O₂, found naturally in tea and coffee plants, which acts as a mild stimulant on the central nervous system.

Recorded use

Wiktionary examples

These source excerpts show how caffeine appears in context. They illustrate usage; the definition above remains the entry’s reference meaning.

  1. For example, 0.100 grams of caffeine yield by combustion, by weight, 0.180 grammes of carbonic acid.
  2. Hitherto, in consequence of its slight solubility, caffeine has been administered hypodermically only in very small doses ; in fact, at the ordinary temperature, it requires 93 parts of water to dissolve, so that a cubic centimeter would contain scarcely more than a centigram.

Etymology

Borrowed from French caféine, from café (“coffee”), or German Caffein, Kaffein (cp. Coffein, Koffein), from Kaffee (“coffee”) (cp. Kaffe, Koffee, Koffe), or Italian caffè (“coffee”) + -ine.

This word in other languages

cafeína(Español)caféine(Français)Koffein(Deutsch)cafeína(Português)

Common misspellings

Also misspelled as:

  • acffeine
  • cafefine
  • cafeine
  • caffeien
  • caffeinne
  • caffenie
  • caffiene
  • ccaffeine
  • cfafeine

Misspelling Pattern Breakdown

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

acffeine2cafefine2cafeine1caffeien2caffeinne1caffenie2caffiene2ccaffeine1
Edit distance from "caffeine"

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 "caffeine"?
"caffeine" is spelled C-A-F-F-E-I-N-E. The IPA pronunciation is /ˈkæfiːn/.
What does "caffeine" mean?
As a noun, "caffeine" means: An alkaloid, C₈H₁₀N₄O₂, found naturally in tea and coffee plants, which acts as a mild stimulant on the central nervous system.
What are common misspellings of "caffeine"?
Common misspellings include "acffeine", "cafefine", "cafeine", "caffeien", "caffeinne". The correct spelling is "caffeine".
How do you pronounce "caffeine"?
The IPA (International Phonetic Alphabet) transcription for "caffeine" is /ˈkæfiːn/. 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 "caffeine"?
Borrowed from French caféine, from café (“coffee”), or German Caffein, Kaffein (cp. Coffein, Koffein), from Kaffee (“coffee”) (cp. Kaffe, Koffee, Koffe), or Italian caffè (“coffee”) + -ine. 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 "caffeine", not the corpus desk frequency band.

Same letter count

Frequency-ranked English headwords with 8 letters (nearest by frequency rank).

blankets#11,657believer#11,655barracks#11,651airborne#11,646

Similar misspelling depth

Headwords with a similar count of attested misspellings (9 here; floor ≥5).

bunker9 variantsbakery9 variantscoward9 variantsadvent9 variants

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

Source: FrequencyWords open word-frequency list