rad

¹

[ rad ]

noun

, Physics.

1. a unit of absorbed dose of radiation equal to 0.01 gray: not a standard SI unit, the rad is still used, especially in the U.S., but it is increasingly disfavored.

rad

²

[ rad ]

noun

1. Informal. a radical, especially a person with extreme views on political and social issues.

adjective

, rad·der, rad·dest.

1. Slang. excellent; wonderful; cool:

   a high speed, high energy, totally rad racing game.

rad

³

[ rad ]

abbreviation for

, Mathematics.

1. radian; radians.

rad.

⁴

abbreviation for

, Mathematics.

1. radical.
2. radix.

rad

¹

/ ræd /

noun

1. a former unit of absorbed ionizing radiation dose equivalent to an energy absorption per unit mass of 0.01 joule per kilogram of irradiated material. 1 rad is equivalent to 0.01 gray

rad

²

symbol for

1. radian

rad.

³

abbreviation for

1. radical
2. radius

rad

/ răd /

1. A unit used to measure energy absorbed by a material from radiation. One rad is equal to 100 ergs per gram of material. Many scientists now measure this energy in grays rather than in rads.

rad

1. An acronym for r adiation a bsorbed d ose. A unit of energy absorbed from ionizing radiation .

Word History and Origins

Origin of rad¹

First recorded in 1915–20; r(adiation) a(bsorbed) d(ose)

Origin of rad²

First recorded in 1820–25 rad ²for 1; 1975–80 rad ²for 2; shortening of radical

Origin of rad³

First recorded in 1910–15; shortening

Word History and Origins

Origin of rad¹

C20: shortened from radiation

Example Sentences

He had spent about two minutes exposed to a radiation field he estimated at 2,000 rads per hour, enough to make a person ill.

From Popular-Science

When I put them on my feet, it’s time to go do something rad.

From Outside Online

I believe that if we start honoring mental health like we honor getting rad in the mountains, lives will be saved.

From Outside Online

Gardening is far less “rad” than running 50 miles or climbing sandstone, after all.

From Outside Online

I wouldn’t say I’m a rad skier now, but I can ski at moderate speed and feel confident and not like I’m a hazard to myself or to others.

From Outside Online

Jim really paved the way—on film and in television—for people to see young, rad chicks kick ass and take names.

From The Daily Beast

If Hugh Jackman is totally heterosexual, his mode is a confusing—and not in a good, rad way—butch-camp.

From The Daily Beast

Nashville: Broadman Holman Publishers, 1996 Rad, Gerhard von.

From The Daily Beast

In October 2007, Hourani launched his first ready-to-wear unisex line, RAD by Rad Hourani, at a small art gallery in Paris.

From The Daily Beast

The ‘Today’ Show Horses Around Who knew David Gregory was such a rad dancer?

From The Daily Beast

Since ginger is not stated to be one of the ingredients of the compound, it, perhaps, may be the mysterious stranger latalia rad.

From Project Gutenberg

Professor Day reports that he was unable to find any mention of the drug of latalia rad.

From Project Gutenberg

This would seem to indicate that what has already been intimated by The Journal—​namely, that latalia rad.

From Project Gutenberg

This seems very open and above board, except as to quantities, until one tries to find out what latalia rad.

From Project Gutenberg

Experts to whom this remedy was submitted were unable even to find mention of such a drug or plant as latalia rad.

From Project Gutenberg

Related Words

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• remarkable
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