diffuser

noun

dif·​fus·​er di-ˈfyü-zər How to pronounce diffuser (audio)
plural diffusers
1
: one that diffuses: such as
a
: a device (such as a reflector) for distributing the light of a lamp evenly
b
: a screen (as of cloth or frosted glass) for softening lighting (as in photography)
c
: a device (such as slats at different angles) for deflecting air from an outlet in various directions
d
: a device that produces a fine mist of water and often essential oils
2
: a device for reducing the velocity and increasing the static pressure of a fluid passing through a system

Examples of diffuser in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Barajas steers away from newer methods like using a diffuser or autoclave in her process and uses American whiskey barrels for the product’s 6-month resting process. Carley Rojas Ávila, Forbes.com, 19 Sep. 2025 The power button, on the top panel and metal-skinned, features a power-on indicator LED behind a small rectangular plastic diffuser. PC Magazine, 14 Sep. 2025 Adaptive underbody front diffusers direct air to minimize drag or increase engine cooling, as needed. Mark Phelan, USA Today, 7 Sep. 2025 Adaptive underbody front diffusers direct air to minimize drag or increase engine cooling, as needed. Mark Phelan, Freep.com, 4 Sep. 2025 See All Example Sentences for diffuser

Word History

First Known Use

1645, in the meaning defined at sense 1

Time Traveler
The first known use of diffuser was in 1645

Browse Nearby Words

Cite this Entry

“Diffuser.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/diffuser. Accessed 26 Sep. 2025.

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!