diffuse

American  

[dih-fyooz, dih-fyoos] / dɪˈfyuz, dɪˈfyus /

verb (used with object)

diffused, diffusing

1. to pour out and spread, as a fluid.

2. to spread or scatter widely or thinly; disseminate.

3. Physics. to spread by diffusion.

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verb (used without object)

diffused, diffusing

1. to spread.

2. Physics. to intermingle by diffusion.

adjective

1. characterized by great length or discursiveness in speech or writing; wordy.

2. widely spread or scattered; dispersed.

3. Botany. widely or loosely spreading.

4. Optics. (of reflected light) scattered, as from a rough surface (specular ).

diffuse British  

/ dɪˈfjuːzəbəl, dɪˈfjuːslɪ /

verb

1. to spread or cause to spread in all directions

2. to undergo or cause to undergo diffusion

3. to scatter or cause to scatter; disseminate; disperse

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adjective

1. spread out over a wide area

2. lacking conciseness

3. (esp of some creeping stems) spreading loosely over a large area

4. characterized by or exhibiting diffusion

   diffuse light

   diffuse reflection

5. botany (of plant growth) occurring throughout a tissue

Commonly Confused

See defuse

Other Word Forms

• diffusely adverb
• diffuseness noun
• diffusibility noun
• diffusible adjective
• interdiffuse verb
• nondiffuse adjective
• nondiffused adjective
• nondiffusing adjective
• overdiffuse verb
• overdiffusely adverb
• overdiffuseness noun
• rediffuse verb
• undiffused adjective
• well-diffused adjective

Etymology

Origin of diffuse

1350–1400; Middle English (< Anglo-French ) < Latin diffūsus spread, poured forth. See dif-, fuse ²

Example Sentences

While few dispute the potential for AI to remake the business-software sector—along with virtually every facet of the economy—most believe the impacts will be more diffuse and delayed than this week’s selloff suggested.

From The Wall Street Journal • Feb. 7, 2026

Oil prices tumbled 4% early Monday as President Donald Trump said Iran was “seriously talking” with the U.S. in a bid to diffuse geopolitical tensions.

From Barron's • Feb. 2, 2026

In order to further diffuse tensions, Zubaidi and an STC delegation had been due to fly from Aden to Riyadh on Tuesday night for talks with the government.

From BBC • Jan. 7, 2026

"Other vaccines can cause myocarditis and inflammatory problems, but the symptoms tend to be more diffuse," Wu said.

From Science Daily • Dec. 27, 2025

For a while I saw Faxe’s profile rigid as pale stone in a diffuse dust of light.

From "The Left Hand of Darkness" by Ursula K. Le Guin