diffuser

American  

[dih-fyoo-zer] / dɪˈfyu zər /

Or diffusor

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.

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diffuser British  

/ 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

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Etymology

Origin of diffuser

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

Example Sentences

The fundamental aerodynamic philosophy is a return to so-called 'step-plane' cars, with a flat bottom either side of the central chassis reference plane, with a diffuser at the back.

From BBC

It recently installed scent diffusers with its Fresh Balsam fragrance in New York City’s Grand Central Terminal to accompany its messaging for four weeks.

From The Wall Street Journal

Scents of lavender spit out from oil diffusers placed strategically throughout the venue.

From Literature

“From forecasting demand and budgeting to producing our candles, diffusers and seasonal gift collections months in advance.”

From MarketWatch

When it comes to smell, use a diffuser with essential oils like lavender which can help you relax.

From BBC