diffuser

or dif·fu·sor

[ dih-fyoo-zer ]

noun

1. a person or thing that diffuses.
2. (in various machines or mechanical systems, as centrifugal pumps or compressors) a device for utilizing part of the kinetic energy of a fluid passing through a machine by gradually increasing the cross-sectional area of the channel or chamber through which it flows so as to decrease its speed and increase its pressure.
3. (in a lighting fixture) any of a variety of translucent materials for filtering glare from the light source.
4. a pierced plate or similar device for distributing compressed air for aeration of sewage.

diffuser

/ dɪˈfjuːzə /

noun

1. a person or thing that diffuses
2. a part of a lighting fixture consisting of a translucent or frosted covering or of a rough reflector: used to scatter the light and prevent glare
3. a cone, wedge, or baffle placed in front of the diaphragm of a loudspeaker to diffuse the sound waves
4. a duct, esp in a wind tunnel or jet engine, that widens gradually in the direction of flow to reduce the speed and increase the pressure of the air or fluid
5. photog a light-scattering medium, such as a screen of fine fabric, placed in the path of a source of light to reduce the sharpness of shadows and thus soften the lighting
6. a perforated plate or similar device for distributing compressed air in the aeration of sewage
7. a device, attached to a hairdryer, which diffuses the warm air as it comes out

Word History and Origins

Origin of diffuser¹

First recorded in 1670–80; diffuse + -er ¹

Example Sentences

Ripple calls their vapes “aromatic diffusers” and notes they are vegan and cruelty free.

From Los Angeles Times

"He brought a scented diffuser, his own mattress topper, a waffle maker so he could make the breakfast he normally would have," Wightman says.

From BBC

But the efficacy of diffusers can vary, depending on the species of mosquito.

From Los Angeles Times

If you have them, look for diffusers and bulbs that offer warm colors — for LEDs, the color temperature should be a warm white of about 2,700 Kelvin — and make sure you have dimmers.

From Seattle Times

Capsules of dry concentrate were projected from diffusers under every third seat.

From Los Angeles Times