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 key lies in a fast oscillating sheet known as a diffuser, onto which synchronous images are projected at high speed (2,880 images per second) and at different heights; human persistence of vision ensures that these images are perceived as true 3D objects. —ArsTechnica, 30 Apr. 2025

And kudos to Poppy Thompson and Neil Carnation for cleaning up that whole mess, recycling the yogurt containers, and installing an aromatherapeutic lemongrass-oil diffuser. —Will Eno, New Yorker, 17 Apr. 2025

For curly or wavy hair, blow dry the fringe with a diffuser, separating strands with fingers to create a messy fringe and set with product. —Irene Coltrinari, Vogue, 1 Apr. 2025

If a house full of teenagers has the living room smelling like gym bags and snack wrappers, this aromatherapy diffuser is the effortless way to bring a bit of spa-like calm (and much better scent) back into her space. —Christa Joanna Lee, Glamour, 15 Apr. 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