dif·fus·er | \di-ˈfyü-zər \

Definition of diffuser 

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

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

There are active aero flaps in the hood, the front splitter, and the rear diffuser; the articulating rear wing can act as an active air brake; and the car’s underside is completely smooth and flat. Tony Markovich, Car and Driver, "With 1888 HP, the Rimac C_Two Puts Croatia on the Supercar Map," 7 Mar. 2018 From electronic diffusers to plug-in fresheners, there's no shortage of ways to make our homes smell good. Kelsey Kloss, ELLE Decor, "Home Fragrances: A Brief History, From Ancient Egypt To Today," 5 Aug. 2016 There's a new front diffuser and a much bigger rear wing. Jonathan M. Gitlin, Ars Technica, "Faster than an F1 car: Porsche is breaking records with the 919 Hybrid," 9 Apr. 2018 Spray a bunch in and scrunch the hair with your hands or dry with a diffuser for lots of kinky fun curl. Kaitlyn Frey, PEOPLE.com, "Shop Every Beauty Product Drew Barrymore Swears By," 24 May 2018 In the process of turning the appliance off, some of the vapor from the diffuser must have sprayed onto my face. Lauren Smith, Good Housekeeping, "Woman Claims Her Face Was Severely Burned in Essential Oil Diffuser Accident," 17 Nov. 2017 The carbon continues with optional front fender vents, side strakes, a rear lip spoiler, and an aggressive rear diffuser. Tony Markovich, Car and Driver, "Cookin’ with Carbon: ABT Sportsline Unleashes 530-HP Audi RS5-R," 26 Jan. 2018 Some examples include depositing a check on your banking app, putting spare shoes by the door away, and filling up and flipping on that new aromatherapy diffuser. Southern Living, "The 60-Second Trick to Acing Your To-Do List," 26 June 2018 At this height the Senna’s double diffuser is fully entrained (higher downforce and less drag) due to a phenomenon pilots know as ground effects. Dan Neil, WSJ, "2019 McLaren Senna: A Pet Racecar for Billionaires," 31 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'diffuser.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of diffuser

1645, in the meaning defined at sense 1

History and Etymology for diffuser

diffuse entry 2 + -er entry 2

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Statistics for diffuser

Last Updated

11 Oct 2018

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Time Traveler for diffuser

The first known use of diffuser was in 1645

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