adjective dif·fuse \di-ˈfyüs\

: spread out over a large space : not concentrated in one area

Full Definition of DIFFUSE

:  being at once verbose and ill-organized <a diffuse report from the scene of the earthquake>
:  not concentrated or localized <diffuse lighting><diffuse sclerosis>
dif·fuse·ly adverb
dif·fuse·ness noun

Examples of DIFFUSE

  1. The forest was filled with a soft, diffuse light.
  2. <a diffuse speech that took a great deal of time to make a very small point>

Origin of DIFFUSE

Middle English, from Latin diffusus, past participle of diffundere to spread out, from dis- + fundere to pour — more at found
First Known Use: 15th century

Synonym Discussion of DIFFUSE

wordy, verbose, prolix, diffuse mean using more words than necessary to express thought. wordy may also imply loquaciousness or garrulity <a wordy speech>. verbose suggests a resulting dullness, obscurity, or lack of incisiveness or precision <the verbose position papers>. prolix suggests unreasonable and tedious dwelling on details <habitually transformed brief anecdotes into prolix sagas>. diffuse stresses lack of compactness and pointedness of style <diffuse memoirs that are so many shaggy-dog stories>.


verb dif·fuse \di-ˈfyüz\

: to spread out : to move freely throughout a large area

: to exist or be known throughout an area

: to cause (light) to be soft and spread out


Full Definition of DIFFUSE

transitive verb
a :  to pour out and permit or cause to spread freely
b :  extend, scatter
c :  to spread thinly or wastefully
:  to subject to diffusion; especially :  to break up and distribute (incident light) by reflection
intransitive verb
:  to spread out or become transmitted especially by contact
:  to undergo diffusion
dif·fus·ible \di-ˈfyü-zə-bəl\ adjective

Examples of DIFFUSE

  1. The heat from the radiator diffuses throughout the room.
  2. The heat was diffused throughout the room.
  3. The photographer uses a screen to diffuse the light.
  4. an area of diffused light

Origin of DIFFUSE

Middle English diffused, past participle, from Latin diffusus, past participle
First Known Use: 14th century
DIFFUSENESS Defined for Kids


verb dif·fuse \di-ˈfyüz\

Definition of DIFFUSE for Kids

:  to spread or allow to spread freely <The frosted window diffused the sunlight.>


Next Word in the Dictionary: diffuse nebulaPrevious Word in the Dictionary: diffractometerAll Words Near: diffuse
How to use a word that (literally) drives some people nuts.
Test your vocab with our fun, fast game
Ailurophobia, and 9 other unusual fears