Etymograph

English

diffusion

Diffusion comes from Latin diffūsiō ‘spreading out, increase in extent or breadth’, from diffundō ‘to diffuse, scatter’, and ultimately from Proto-Indo-European *ǵʰewd- ‘to pour’.

  1. Proto-Indo-Europeanc. 4500–2500 BCE*ǵʰewd-1‘to pour’reconstructed
  2. Proto-Indo-Europeanc. 4500–2500 BCE*ǵʰunédti1reconstructed
  3. Proto-Italicc. 1500–700 BCE*hundō1‘to pour out’reconstructed
  4. Latinc. 75 BCE–200 CEfundō1‘to pour out, shed’
  5. Latinc. 75 BCE–200 CEdiffundō2‘to diffuse, scatter’
  6. Latinc. 75 BCE–200 CEdiffūsiō2‘spreading out, increase in extent or breadth’
  7. Englishearliest quotation 1907diffusion2

attested reconstructed ? uncertain or disputed deepest recorded ancestor

  1. 1 Wiktionary, Latin diffundo
  2. 2 Wiktionary, English diffusion
  3. Earliest quotation in Wiktionary’s entry: 1907, Ronald M. Burrows, The Discoveries In Crete: “Even the false-necked vase, though it reaches its widest…”.

Lineage

  1. Proto-Indo-Europeanc. 4500–2500 BCE*ǵʰewd-Wiktionary, Latin diffundo‘to pour’reconstructed
  2. Proto-Indo-Europeanc. 4500–2500 BCE*ǵʰunédtiWiktionary, Latin diffundoreconstructed
  3. Proto-Italicc. 1500–700 BCE*hundōWiktionary, Latin diffundo‘to pour out’reconstructed
  4. Latinc. 75 BCE–200 CEfundōWiktionary, Latin diffundo‘to pour out, shed’
  5. Latinc. 75 BCE–200 CEdiffundōWiktionary, English diffusion‘to diffuse, scatter’
  6. Latinc. 75 BCE–200 CEdiffūsiōWiktionary, English diffusion‘spreading out, increase in extent or breadth’
  7. Englishearliest quotation 1907diffusionWiktionary, English diffusion. Earliest quotation in Wiktionary’s entry: 1907, Ronald M. Burrows, The Discoveries In Crete: “Even the false-necked vase, though it reaches its widest…”

Linked words

through Proto-Indo-European *ǵʰewd- ‘to pour’

yet, refuse, gut, font, fuse, effusive, 41 more

through Proto-Italic *hundō ‘to pour out’

confused, foundry, fondue, 37 more

through Latin fundō ‘to pour out, shed’

foundation, founder, fundamental, refund, confusion, funnel, confuse, confound, infusion, infuse, perfusion, profusion, effusion, 43 more

Today it means

noun The act of diffusing or dispersing something, or the property of being diffused or dispersed; dispersion.

Sources

Sources: Wiktionary, “diffusion”; the older steps come from the Wiktionary entry for Latin diffundo. By Wiktionary contributors, CC BY-SA 4.0, via kaikki.org (dump of Oct 3 2026); text adapted and restructured. Language periods are conventional ranges, not dates for this word. License.

Etymograph / Proto-Indo-European *ǵʰewd- / diffusion

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