Impeller vs Diffuser - What's the difference?

As nouns the difference between impeller and diffuser

is that impeller is something which or someone who impels, usually a part of a pump while diffuser is any person or thing that diffuses.

(wikipedia impeller)

(en noun)

Something which or someone who impels, usually a part of a pump.

(en noun)

Any person or thing that diffuses.

A device designed to diffuse a scent efficiently.

* {{quote-news, year=2009, date=February 28, author=Rita Zekas, title=DecoRita visits West Elm, work=Toronto Star citation

, passage=They are in the under-$20 section, which includes a display of scented candles and diffusers . }}

(optics) Any device that or spreads out or scatters light, making the light appear softer.

* {{quote-news, year=2008, date=January 24, author=, title=In a Town Known for Light, a House With Very Little, work=New York Times citation

, passage=Along the sofa every three and a half feet, fluorescent tubes glow through translucent plastic diffusers . }}

(automotive) A shaped section of a car's underbody which improves the car's aerodynamic properties.

(thermodynamics) A mechanical device that is designed to control the characteristics of a fluid at the entrance to a thermodynamic open system.

(sewage treatment) An aerating device consisting of a membrane with fine pores, through which air is blown to generate small bubbles.

(cooking) A cooking item that can be placed above a stove heating element or burner to separate the cooking utensil from the heat source.

A hairdryer attachment that diffuses the flow of air.