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 lower half of the vehicle features a sculptural shape that calls to the mind the curvaceous C3, with prominent air intakes up front and an even larger diffuser in the back. —Bryan Hood, Robb Report, 7 Apr. 2025

What’s more, the thoughtful design offers easy installation, adjustable spray, and even aromatherapy diffusers if that’s your steez. —Simon Hill, Wired News, 31 Mar. 2025

Humidifiers, essential oil diffusers and noise technology aren’t just gimmicks of the sleep industry. —Dahvi Shira, Forbes.com, 31 Mar. 2025

In one study from 2009, his team ordered special concentrated essential oils made from Japanese cypress trees and then pumped them into the hotel rooms of test subjects using a diffuser. —Malaka Gharib, NPR, 14 Mar. 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