A combination of two slang words "sick" and "rad" (short for radical). Sicrad combines the two words to create a word describing something good, something cool, something awesome!
Did you see that wave man? It was sicrad!
Woa, check out that dude on the skate bowl; that was a sicrad ollie to backside air!
Guy watching the surf report sees that tomorrows swell is 8ft with offshore winds. He exclaims "SICKRAD!!" to display his excitement.