diffusion
noun
dif·fu·sion
di-ˈfyü-zhən 
1
: the state of being spread out or transmitted especially by contact : the action of diffusing
the diffusion of knowledge
2
3
a
chemistry
: the process whereby particles of liquids, gases, or solids intermingle as the result of their spontaneous movement caused by thermal (see thermal entry 1 sense 1b) agitation and in dissolved substances move from a region of higher to one of lower concentration
b
physics
(1)
: reflection of light by a rough reflecting surface
(2)
: transmission of light through a translucent material : scattering
4
: the spread of cultural elements from one area or group of people to others by contact
5
photography
: the softening of sharp outlines in an image
Examples of diffusion in a Sentence
the author's tendency toward diffusion makes the novel a tedious read
Recent Examples on the Web
The diffusion cycle involves multivoltine mosquitoes, especially Anopheles species, which produce several broods across the summer.
—
John Drake,
Forbes.com,
4 July 2026
Other people emphasize the rules and regulations slowing down diffusion and stymieing change.
—
Annie Lowrey,
The Atlantic,
29 June 2026
To accelerate this diffusion, collaboration between government, business, civil society, and academia will be vital to share risks, smooth the path to market, and ensure that technological breakthroughs have a positive impact on societies.
—
Alois Zwinggi,
Time,
24 June 2026
Rapid volumetric heating accelerates dye diffusion and allows for deeper penetration of the prickly pear peel pigment molecules (betalain) into the wool fiber interior swollen by the heat.
—
Jennifer Bringle,
Footwear News,
17 June 2026
See All Example Sentences for diffusion
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John Drake,
Forbes.com,
4 July 2026
Other people emphasize the rules and regulations slowing down diffusion and stymieing change.
—
Annie Lowrey,
The Atlantic,
29 June 2026
To accelerate this diffusion, collaboration between government, business, civil society, and academia will be vital to share risks, smooth the path to market, and ensure that technological breakthroughs have a positive impact on societies.
—
Alois Zwinggi,
Time,
24 June 2026
Rapid volumetric heating accelerates dye diffusion and allows for deeper penetration of the prickly pear peel pigment molecules (betalain) into the wool fiber interior swollen by the heat.
—
Jennifer Bringle,
Footwear News,
17 June 2026
See All Example Sentences for diffusion
Cite this Entry
“Diffusion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/diffusion. Accessed 6 Jul. 2026.
Copy CitationKids Definition
diffusion
noun
dif·fu·sion
dif-ˈyü-zhən
1
: a diffusing or a being diffused
2
: the mixing of particles of liquids, gases, or solids so that they move from a region of high concentration to one of lower concentration
3
: the scattering of light by reflection from a rough surface or by passage through a translucent material (as frosted glass)
Medical Definition
diffusion
noun
dif·fu·sion
dif-ˈyü-zhən
1
: the process whereby particles of liquids, gases, or solids intermingle as the result of their spontaneous movement caused by thermal agitation and in dissolved substances move from a region of higher to one of lower concentration
2
a
: reflection of light by a rough reflecting surface
b
: transmission of light through a translucent material
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