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rad 1

A unit of energy absorbed from ionizing radiation, equal to 100 ergs per gram or 0.01 joule per kilogram of irradiated material. It has been replaced as a standard scientific unit by the gray.

[r(adiation) a(bsorbed) d(ose).]

rad 2

adj. Slang
Excellent; wonderful.

[Short for radical.]

rad 3



(Units) 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
[C20: shortened from radiation]


symbol for
(Units) radian



n. Physics.
a unit of absorbed dose equal to 0.01 Gy. Compare dose (def. 4).
[1915–20; shortening of radiation]



1. Informal. a radical.
2. Slang. fine; wonderful.
[1820–30; shortening of radical]




1. radical.
2. radix.


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.


1. A unit of radiation absorbed from a radioactive source.
2. A short form of radian, a unit of measure for plane angles. See centrad.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.rad - a unit of absorbed ionizing radiation equal to 100 ergs per gram of irradiated material
radioactivity unit - a measure of radioactivity
2.rad - the unit of plane angle adopted under the Systeme International d'Unites; equal to the angle at the center of a circle subtended by an arc equal in length to the radius (approximately 57.295 degrees)
angular unit - a unit of measurement for angles
milliradian - a unit of angular distance equal to one thousandth of a radian
References in classic literature ?
Rad wanted to do it all alone, but Koku said he was like a baby now.
If old Rad were here now, I'd tell him to jump overboard and scatter 'em.
RAD is integrating D-NFV into its Megaplex-4 Next-Generation Multiservice Access Node, widely used by power utilities for substation connectivity, protection, and automation communications, and operational core networks.
To date, the efficacy of the RAD has not been tested.
Richardson, a fervent campaigner for better teaching and dancing) published what became the RAD foundation: Edouard Espinosa's teaching syllabus based on the lore of past masters from Beauchamps in the seventeenth century to Petipa two centuries later.
The RAD University website, which can be accessed from the RAD Data Communications home page at www.
Located in Beer Sheva, the “capital” of Israel's Negev region, the initiative is being funded jointly by RAD and the Office of the Chief Scientist, an agency within the country's Ministry of Economics, which together are investing approximately $32 million in the project over the next three years.
Delphi for PHP brings RAD productivity benefits to PHP Web developers that Delphi users have enjoyed for years.
Solidly standing behind the broad range of access and backhaul equipment that it offers to service providers and enterprises, RAD significantly upped the ante from its previous one-year hardware warranty to the five full years of coverage that went into effect on January 1, 2012.
The international summer school classes are normally held at the headquarters of the RAD, which is situated by the River Thames in Battersea, London.
RAD and BroadLight are co-marketing the pseudowire-over-GPON solution to telecommunications system vendors and service providers worldwide.
FONEX has been a RAD VAR for 14 years in RAD's active channel sales program.