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

Candles, diffusers, room sprays and incense are increasingly chosen for their vessels and packaging as much as their scent, functioning as visible aesthetic objects within a room. — Lauren Jarvis-Gibson, Fort Worth Star-Telegram, 6 Oct. 2026

There have also been car technical rows here — a Ferrari bargeboard saga after that 1999 race and a key protest of 2009’s double-diffuser gate. — Alex Kalinauckas, New York Times, 2 Oct. 2026

Alongside wireless lamps and smart calendars, the current shortlist includes candle warmer lamps, heated throw blankets, essential-oil diffusers, sunrise alarm clocks and rainfall showerheads. — Lauren Jarvis-Gibson, Charlotte Observer, 30 Sep. 2026

Relocate everything else, and finish by adding a small, wind-down treat like a soothing candle, diffuser, or stylish carafe. — Jamie Cuccinelli, Martha Stewart, 25 Sep. 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