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rad

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The definition of rad is slang for an excellent person or thing.

(adjective)

An example of rad is a bright sunny day spent with friends; a rad day.

Rad is defined as a unit of energy that has been absorbed from radiation.

(noun)

An example of a rad is four doses of radiation absorbed into the skin.

See rad in Webster's New World College Dictionary

noun

a basic unit of an absorbed dose of radiation, equal to the absorption of 100 ergs of energy per gram of material or 0.01 joule per kilogram of material (0.01 gray or 1.1 roentgen)

Origin: < rad(iation)

radian(s)
radical
radius
radix

See rad in American Heritage Dictionary 4

noun

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

Origin:

Origin: r(adiation) a(bsorbed) d(ose)

adjective
Slang

Excellent; wonderful.

Origin:

Origin: Short for radical

abbreviation

radian

abbreviation
Mathematics