\ˈrad \

Definition of rad 

(Entry 1 of 3)

: a unit of absorbed dose of ionizing radiation equal to an energy of 100 ergs per gram of irradiated material



Definition of rad (Entry 2 of 3)

Definition of rad (Entry 3 of 3)

1 radian

2 radius

3 radix

Examples of rad in a Sentence

Recent Examples on the Web: Noun

The news sent the shares of drugstore giants CVS Health (cvs, -9.28%), Walgreens Boots Alliance (wba, -9.34%), and Rite Aid (rad, -9.09%) plunging between 8% and 10%. Phil Wahba, Fortune, "Walgreens and CVS Shares Plunge After Amazon Announces Deal to Buy Online Pharmacy PillPack," 28 June 2018 The TRD Pro amplifies those feelings by a factor of rad. Andrew Wendler, Car and Driver, "2019 Toyota 4Runner TRD Pro: Be a Tough Guy, or Just Look Like One," 8 Feb. 2018 There’s so much rad s— happening right now in music. Dave Quinn, PEOPLE.com, "WATCH: Pink Tells Daughter ‘We Don’t Change’ in Inspiring Speech About Self-Acceptance at MTV VMAs," 28 Aug. 2017

Recent Examples on the Web: Adjective

But thanks to a new stable of pop-up merch slingers from coast to coast—like the GX1000 crew, pictured here, whose rad five-panels rep their hometown of San Francisco—standard-issue five-panels feel fresher than ever. The Editors Of Gq Style, GQ, "The 15 Raddest Dad Caps to Wear This Summer," 26 Apr. 2018 Rookie has a fairly straightforward mission: to speak honestly with teenagers and give them rad things to look at and think about. Amy Rose Spiegel, The Cut, "I Think About This a Lot: The ’90s Computer Game Chop Suey," 26 Feb. 2018 If the new Star Wars trilogy hasn't been exciting enough, the recent launch of various comic books — most of them pretty rad — have fleshed out stories not seen in the movies. Brian Truitt, USA TODAY, "Happy Star Wars Day! Here are 6 ways to celebrate #MayThe4th and get ready for 'Solo'," 3 May 2018 As an alternative, interested US gearheads can instead get something just as rad while avoiding those issues: a Hilux Surf. Devin Holody, Ars Technica, "A beginner’s guide to the world of weird and wonderful Japanese import cars," 26 Apr. 2018 Dusty’s first look was rough, but her winter dress with the frozen heart and her metal outfit, to me, were rad! Stephen Daw, Billboard, "'RuPaul's Drag Race' Season 10, Ep. 4: Climate Change, Nicki Minaj Lip Sync & More," 13 Apr. 2018 The fact that @CocaCola acknowledged they/them pronouns during the SUPERBOWL was rad as hell. Stephen Daw, Billboard, "Coca-Cola Uses Gender Neutral Pronouns In Inclusive Super Bowl Commercial," 5 Feb. 2018 Twelve different colors are on offer, including a matte-gray finish that looks rad but adds $3950 to the bottom line. Michael Simari, Car and Driver, "2017 Mercedes-Benz E-class Wagon," 14 Dec. 2017 Some historical and cultural context would've been rad too, BUT LET'S NOT GET CRAZY ABOUT IT. Lauren Hoffman, Cosmopolitan, "Khloé Worries About Lamar After He Asks to Borrow Cash on Keeping Up With the Kardashians," 1 Aug. 2016

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'rad.' 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 rad


circa 1953, in the meaning defined above


1982, in the meaning defined above

History and Etymology for rad


radiation absorbed dose

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Statistics for rad

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Time Traveler for rad

The first known use of rad was circa 1953

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More Definitions for rad



English Language Learners Definition of rad

: very appealing or good


\ˈrad \

Medical Definition of rad 

(Entry 1 of 2)

: a unit of absorbed dose of ionizing radiation equal to an energy of 100 ergs per gram of irradiated material

Medical Definition of rad (Entry 2 of 2)

root used in writing prescriptions

History and Etymology for rad


Latin radix

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Comments on rad

What made you want to look up rad? Please tell us where you read or heard it (including the quote, if possible).


to express warning or disapproval

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