diffusion

/dɪˈfjuː.ʒən/

//dɪˈfjuː.ʒən// noun

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

"diffusion" is a 9-letter English headword indexed on PlainSpell.

The verdict

“diffusion” is a moderately-common English word, ranked #17,120 in English word frequency and used as a noun.

#17,120
frequency rank, English
9
letters
12
tracked misspellings

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - The act of diffusing or dispersing something, or the property of being diffused or dispersed; dispersion.

Key facts for diffusion
PropertyValue
Headworddiffusion
LanguageEnglish
Part of speechNoun
IPA/dɪˈfjuː.ʒən/
Letters9
Frequency rank#17,120
Misspellings tracked12
Confusable pairs0
SourceWiktionary (kaikki.org)

Where “diffusion” sits in English frequency

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

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

Scale is logarithmic (each tick is 10× rarer). Source: FrequencyWords open word-frequency list.

Spelling & Dictionary Insight

The English entry for diffusion is 9 letters long, classified as a noun, and transcribed in the International Phonetic Alphabet as /dɪˈfjuː.ʒən/. Corpus data places it at rank #17,120 in overall English word frequency, marking it as uncommon enough that many writers pause before typing it. Wiktionary records 7 distinct senses for this headword, so context determines which meaning a reader should apply.

Our generated misspelling index lists 12 likely wrong-spelling variants for diffusion, with forms such as "ddiffusion", "dfifusion", and "diffsuion". 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. Our dataset records no confusable match here, which usually means its spelling is distinct enough that readers don't reach for a similar-looking word instead.

Etymologically, the entry records: Borrowed from Latin diffūsiō, from diffundō; can be decomposed as diffuse + -ion. The correct English form is diffusion, spelled D-I-F-F-U-S-I-O-N.

Definition

  1. 1
    The act of diffusing or dispersing something, or the property of being diffused or dispersed; dispersion.
  2. 2
    The scattering of light by reflection from a rough surface, or by passage through a translucent medium.
  3. 3
    The intermingling of the molecules of a fluid due to random thermal agitation.
  4. 4
    The spread of cultural or linguistic practices, or social institutions, in one or more communities.
  5. 5
    The gradual spread and adoption of goods or services.
  6. 6
    Exchange of airborne media between regions in space in an apparently random motion of a small scale.
  7. 7
    The movement of water vapor from regions of high concentration (high water vapor pressure) toward regions of lower concentration.

Etymology

Borrowed from Latin diffūsiō, from diffundō; can be decomposed as diffuse + -ion.

This word in other languages

difusión(Español)diffusion(Français)Streuung(Deutsch)

Common misspellings

Also misspelled as: ddiffusion,dfifusion,diffsuion,diffuison,diffusino,diffusionn,diffusoin,diffussion,diffution,difufsion,difusion,idffusion

Misspelling Pattern Breakdown

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

ddiffusion1dfifusion2diffsuion2diffuison2diffusino2diffusionn1diffusoin2diffussion1
Edit distance from "diffusion"

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 "diffusion"?
"diffusion" is spelled D-I-F-F-U-S-I-O-N. The IPA pronunciation is /dɪˈfjuː.ʒən/.
What does "diffusion" mean?
As a noun, "diffusion" means: The act of diffusing or dispersing something, or the property of being diffused or dispersed; dispersion.
What are common misspellings of "diffusion"?
Common misspellings include "ddiffusion", "dfifusion", "diffsuion", "diffuison", "diffusino". The correct spelling is "diffusion".
How do you pronounce "diffusion"?
The IPA (International Phonetic Alphabet) transcription for "diffusion" is /dɪˈfjuː.ʒən/. 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 "diffusion"?
Borrowed from Latin diffūsiō, from diffundō; can be decomposed as diffuse + -ion. 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.

Using “diffusion”

The practical upshot for anyone who landed here from a spell-check.

  • The one correct English spelling is D-I-F-F-U-S-I-O-N - every other letter order is a misspelling in standard orthography.
  • Say it as /dɪˈfjuː.ʒən/ (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
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.

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

Source: FrequencyWords open word-frequency list FrequencyWords open word-frequency list