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

Canvas shopping bags, felted trivets and bowls from Tibet, African baskets in many sizes and colors, candles, diffusers and scents are new. —Emily M. Olson, Hartford Courant, 4 Feb. 2026

Quite possibly the answer to my prayers, it’s packed with outrageous markdowns on comfy quilts, calming diffusers, duvet covers, and more. —Jamie Fischer, Better Homes & Gardens, 26 Jan. 2026

In addition, the tailpipes are now thicker and sit above a new diffuser plus what appears to be an additional pair of exhaust pipes at the fringes, pointed down at the ground. —Joel Feder, The Drive, 22 Jan. 2026

The Figuerie candle, vaporizer and diffusers have the celadon packaging. —Jennifer Weil, Footwear News, 21 Jan. 2026

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