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

Each set has slightly different attachments (e.g., the curly set has a diffuser, while the straight and wavy set has second curler size and a flyaway tool), but both are on sale for $100 off. —Boutayna Chokrane, Wired News, 11 July 2025

With five temperature settings (including a cold shot button), three airflow speeds, and six attachments—including a diffuser and smoothing nozzle—you’ve got full control over your blowout. —Christa Joanna Lee, Allure, 5 July 2025

Your bathroom will smell great without candles or diffusers! —Mary Catherine McAnnally Scott, Southern Living, 5 July 2025

The mosquito-repellent system consists of three diffusers (single-use replaceable pods) that offer 330 square feet of coverage via 36 feet of warm-glow string lights. —Mariana Best, Better Homes & Gardens, 19 June 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