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

Now homeowners are chasing that same effect with HVAC scent diffusers — devices that hook into a home’s heating and cooling system to push fragrance through every room at once. —Lauren Jarvis-Gibson, Charlotte Observer, 8 June 2026

Homes often have laundry detergent, dryer sheets, plug-in air fresheners, cleaning sprays, candles or diffusers and HVAC fragrance systems all running together. —Kansas City Star, 8 June 2026

For a smaller home or a single room, a standalone diffuser under $100 may deliver most of the benefit without the commitment. —Lauren Jarvis-Gibson, Sacbee.com, 8 June 2026

Your bathroom will smell great without candles or diffusers! —Mary Catherine McAnnally Scott, Southern Living, 3 June 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