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

The brand creates products, like this car diffuser, that emit delightful fragrances without parabens and phthalates. —Izzy Baskette, PEOPLE, 17 Jan. 2026

The fragrance is meant to last for two to four months without any effort on your part (no lighting candles or plugging in warmers and electric diffusers). —Brittney Morgan, Travel + Leisure, 12 Jan. 2026

And that’s evident in its low-sloping hood, a big rear wing, and a dual-layer diffuser. —New Atlas, 12 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