• synonyms


[verb dih-fyooz; adjective dih-fyoos]
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verb (used with object), dif·fused, dif·fusing.
  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), dif·fused, dif·fusing.
  1. to spread.
  2. Physics. to intermingle by diffusion.
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  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 (opposed to specular).
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Origin of diffuse

1350–1400; Middle English (< Anglo-French) < Latin diffūsus spread, poured forth. See dif-, fuse2
Related formsdif·fuse·ly [dih-fyoos-lee] /dɪˈfyus li/, adverbdif·fuse·ness, nounin·ter·dif·fuse, verb, in·ter·dif·fused, in·ter·dif·fus·ing.non·dif·fuse, adjectivenon·dif·fused, adjectivenon·dif·fus·ing, adjectiveo·ver·dif·fuse, verb, o·ver·dif·fused, o·ver·dif·fus·ing, adjectiveo·ver·dif·fuse·ly, adverbo·ver·dif·fuse·ness, nounre·dif·fuse, verb, re·dif·fused, re·dif·fus·ing.un·dif·fused, adjectivewell-dif·fused, adjective
Can be confuseddefuse diffuse
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Related Words


Examples from the Web for diffuseness

Historical Examples

  • The reason is that Thackeray worked by 'diffuseness of style.'

    Gilbert Keith Chesterton

    Patrick Braybrooke

  • The temptation to diffuseness and irrelevancy is as embarrassing and dangerous.

    Sir Walter Ralegh

    William Stebbing

  • It is, in short, to guard against the confusion that comes from diffuseness.

    Outlines of Educational Doctrine

    John Frederick Herbart

  • The lectures are written in simple style, but suffer from diffuseness.

  • But when poems are paid by the line, bards are pardonable for diffuseness.

British Dictionary definitions for diffuseness


verb (dɪˈfjuːz)
  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 (dɪˈfjuːs)
  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 diffusiondiffuse light; diffuse reflection
  5. botany (of plant growth) occurring throughout a tissue
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Derived Formsdiffusely (dɪˈfjuːslɪ), adverbdiffuseness, noundiffusible (dɪˈfjuːzəbəl), adjectivediffusibility or diffusibleness, noun

Word Origin

C15: from Latin diffūsus spread abroad, from diffundere to pour forth, from dis- away + fundere to pour


Avoid confusion with defuse
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for diffuseness



1520s (transitive), 1650s (intransitive), from Latin diffusus, past participle of diffundere "to pour out or away" (see diffusion). Related: Diffused; diffusing.

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early 15c., from Latin diffusus (see diffuse (v.)).

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Online Etymology Dictionary, © 2010 Douglas Harper

diffuseness in Medicine


  1. Not limited to one tissue or location; widespread.
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  1. To spread or to be spread widely, as through a tissue.
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Related formsdif•fusi•ble (-fyōōzə-bəl) adj.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.