Definition of "rad" []

• 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. (noun)
• Slang Excellent; wonderful. (adjective)
• Radian (abbreviation)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "By the way, is _radix_ perhaps derived from [Sanskrit: rad] (_rad_), a tooth (from the fang-like form of roots), whence _rodere_ and possibly _radius_?"
• "While the word rad is completely outdated it totally applies to this cake."
• "However, I wouldn't call it rad, simply because I wouldn't call anything rad -- never have and never will use that word."