Computer term: "Rapid Application Devolopment" Software used to devolop software easily and fast. RAD software usually does most of the work for you.
See term 2 of IDE.

An abbreviation of 'radical'--a term made popular by the Teenage Mutant Ninja Turtles. Still primarily used by people on the West Coast who find words like 'cool', 'awesome', and 'tight' to be tired and overused; 'rad' is generally considered to be a much higher praise than the aforementioned superlatives. Also used as a general expression of awe.

really cool, but in a more subtle way. as opposed to extreme or awesome. one of the highest compliments you can give someone. being rad is like being cool without having to work for it. it's like a natural coolness.

the word used to describe something when u must describe it as positively as possible. Rad is the strongest alternative, and stronger than the word, 'cool'

Slang and/or abbreviation for the word "radical."

a unit of absorbed dose of ionizing radiation, corresponding to the absorption of 0.01 joule per kilogram of the absorbing material.

Something that is cool, or very neat.

Shortend form of the word radical, a 100% slang word from the 1980's, used mostly in the past by people from Generation-X (people born in the late 60's early 70's) to describe something that's cool.

Apperantly lots teens today are starting to use it as well, most of 'm probably don't even know that it is a 80's slang word and if they do know, they probably are pretending that it's something of their generation.