\ ˈrad How to pronounce rad (audio) \

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

While in town, check out Neon Alley, a rad outdoor art gallery where two dozen neon signs glow. Brittany Anas, The Know, "Stay in a former jail, drive-in theater or goat lodge when visiting Colorado’s most unique hotels," 24 June 2019 The new flow area, designed to the rigorous-rad standards of the Vans Park Series pro tour terrain, offers a deep canyon of banks, bumps and curves that, when navigated correctly, help propel skaters round and round. Barbara Odanaka, latimes.com, "A guide to L.A.’s best skate parks," 7 June 2019 To hit that price, McLaren cut some of the $265,000 650's more expensive hardware (bye-bye, hydraulic anti-roll suspension and active aerodynamics) but the designers were smart enough to keep the rad doors. Ezra Dyer, Popular Mechanics, "The Palace of Perfectionism Where McLaren Supercars Are Born," 12 Feb. 2016 Carpenter kept things graphic and cute for her fitting in rad plaid pieces, but for the big day, upped her game with a fitted militaristic dress punctuated by equally bold accessories. Edward Barsamian, Vogue, "Va-Va-Versace! Sabrina Carpenter Goes Inside the Spectacular Spring Show," 24 Sep. 2018 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

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.

See More

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

Keep scrolling for more

Learn More about rad

Statistics for rad

Look-up Popularity

Time Traveler for rad

The first known use of rad was circa 1953

See more words from the same year

Keep scrolling for more

More Definitions for rad



English Language Learners Definition of rad

US slang : very appealing or good


\ ˈrad How to pronounce rad (audio) \

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

Keep scrolling for more

More from Merriam-Webster on rad

Rhyming Dictionary: Words that rhyme with rad

Nglish: Translation of rad for Spanish Speakers

Britannica English: Translation of rad for Arabic Speakers

Britannica.com: Encyclopedia article about rad

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).


providing supplementary assistance

Get Word of the Day daily email!

Test Your Vocabulary

Farm Idioms Quiz

  • cow coming home
  • What does 'poke' refer to in the expression 'pig in a poke'?
True or False

Test your knowledge - and maybe learn something along the way.

Word Winder's CrossWinder

Test Your Knowledge - and learn some interesting things along the way.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!