Radiclysmic is the theory that anyone or anything reaching "Absolute Radness" would inevitably cause the destruction of the universe through an intricate chain of subspace explosions, due to the overproduction of Rad particles in nearby stars and star clusters. Not unlike division by zero.

If "Absolute Radness" is achieved in deep space with no nearby stars however, it is hypothesized that there would be little to no repercussions. It is also hypothesized that nearby personnel would become "Totally Rad", phasing them out of what is known as "Weak Space", and into another dimension populated by all the raddest things and raddest people.

It's also an adjective to describe something really freaking awesome.
Ex. 1

Kyle: I got all the achievements in Battletoads.

Kyle is phased into Rad Space, destruction of the universe is imminent.

Ex. 2

Kyle: I got all the achievements in Battletoads.

Jeff: Radiclysmic.
by Tom McMot February 17, 2008
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–noun

1. an event so radical, esp. one of a amazing or righteous nature, that produces changes in one's very sense of being.

3. an extensive flood; or deluge of alcohol.
"Brittany's shirt buttons busted at work today unleashing a radiclysm of exposed tits!"
by tho3m January 13, 2010
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–adjective

1. of, pertaining to, or resulting from a radiclysm.

2. of the nature of, or having the effect of, a radiclysm: radiclysmic changes.
"The party last night was radiclysmic."
by tho3m January 13, 2010
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