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

To deal with odors that might seep in from other rooms, buy a few air fresheners or even an essential oil diffuser to help conceal anything offensive. — Bestreviews, Mercury News, 21 Aug. 2026

This kit comes with an aroma sample and a felt diffuser—add a few drops of the Bergamot Tea Blossom scent to further enhance your bathing experience. — Caroline Hughes, Travel + Leisure, 17 Aug. 2026

Some of the most popular forms include peppermint oil diffusers, skin and hair care products, non-toxic insect and vermin repellants, natural cleaning products, dietary supplements and pure essential oil. — Bestreviews, Chicago Tribune, 13 Aug. 2026

Down below is a massive carbon fiber diffuser that, especially in my tester’s stunning Rosso Dino paint, stands out enormously compared to the rest of the car. — Jerry Perez, The Drive, 6 Aug. 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