diffuser

noun

dif·​fus·​er di-ˈfyü-zər 

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

The Rope Light is RGB-addressable and comes in 5m lengths, with a soft silicone diffuser over top that gives it an even glow. —Anthony Karcz, Forbes.com, 20 May 2025

For maximum efficiency, the underbody features a flat plate, and inlets push hot air away from the car while the parabolic line along the side directs airflow toward the rear diffuser. —Kristin Shaw, Popular Science, 7 May 2025

How does a diffuser differ from other hairdryer attachments? —Georgia Day, Vogue, 14 May 2025

Additionally, the company sells laundry care products, plug-in air fresheners and diffusers, as well as men’s body care including cologne and body wash. —Veronica Fernandez-Alvarado, Sacbee.com, 5 May 2025

Word History

Etymology

diffuse entry 2 + -er entry 2

First Known Use

1645, in the meaning defined at sense 1

Rhymes for diffuser

• abuser
• accuser
• boozer
• bruiser
• chooser
• cruiser
• loser
• user
• multiuser