rad

rad

1 [rad]
Compare dose ( def 4a ).


Origin:
1915–20; shortened form of radiation

Dictionary.com Unabridged

rad

2 [rad]
noun
1.
Informal. radical.
adjective
2.
Slang. fine; wonderful.

Origin:
by shortening of radical

rad

Mathematics.
radian; radians.

rad.

Mathematics.
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
Cite This Source Link To RAD
Collins
World English Dictionary
rad1 (ræd)
 
n
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]

rad2
 
symbol for
radian

rad.
 
abbreviation for
1.  radical
2.  radius

Collins English Dictionary - Complete & Unabridged 10th Edition
2009 © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009
Cite This Source
Etymonline
Word Origin & History

rad
"x-ray dose unit," 1918, shortened form of radiation (q.v.). As shortened form of radical (n.), it is attested in political slang from 1820. Teen slang sense of "extraordinary, wonderful" is from late 1970s (see radical).
Online Etymology Dictionary, © 2010 Douglas Harper
Cite This Source
American Heritage
Medical Dictionary

rad 1 (rād)
n.
A unit of energy absorbed from ionizing radiation, equal to 100 ergs per gram or 0.01 joule per kilogram of irradiated material.

rad 2
abbr.
radian

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
Cite This Source
American Heritage
Science Dictionary
rad   (rād)  Pronunciation Key 
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.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
Cite This Source
American Heritage
Cultural Dictionary

rad definition


An acronym for radiation absorbed dose. A unit of energy absorbed from ionizing radiation.

The American Heritage® New Dictionary of Cultural Literacy, Third Edition
Copyright © 2005 by Houghton Mifflin Company.
Published by Houghton Mifflin Company. All rights reserved.
Cite This Source
FOLDOC
Computing Dictionary

RAD definition

programming
Rapid Application Development.

The Free On-line Dictionary of Computing, © Denis Howe 2010 http://foldoc.org
Cite This Source
American Heritage
Abbreviations & Acronyms
rad
  1. radian

  2. radiation absorbed dose

  3. Slang radical (that is, excellent)

RAD
Royal Academy of Dancing
rad.
  1. radical

  2. radius

  3. radix

The American Heritage® Abbreviations Dictionary, Third Edition
Copyright © 2005 by Houghton Mifflin Company.
Published by Houghton Mifflin Company. All rights reserved.
Cite This Source
Encyclopedia Britannica
Encyclopedia

rad

the unit of absorbed dose of ionizing radiation, defined in 1962 by the International Commission on Radiological Units and Measurements as equal to the amount of radiation that releases an energy of 100 ergs per gram of matter. One rad is equal approximately to the absorbed dose delivered when soft tissue is exposed to one roentgen of medium-voltage radiation. "Rad" is derived from "radiation absorbed dose." In 1975 it was replaced by the gray (Gy), equal to 100 rads, in the International System of Units (SI). The rad is used now only in the United States.

Learn more about rad with a free trial on Britannica.com.

Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
Cite This Source
Copyright © 2014 Dictionary.com, LLC. All rights reserved.
  • Please Login or Sign Up to use the Recent Searches feature