An adjective, to describe an object or event that is both Radical, and indeed spectacular. Such things would include firework-powered skateboards and Puppies with jetpacks.
Hey,Joe,did you see that race crash on TV yesterday?" "Sure did, Bob, it was totally radtacular!
An expression of rejoice used in moments of satisfaction, especially to regard something as amazing. Use of this term may make someone, as a side effect, look like a tool.
Theo tried telling Eliza that her hair was radtacular, but she told him to fuck off; he was shaking his hips like a douchebag.
"That's so spectacular, it's rad and hipster. That's... you guessed it! Radtacular!"
A person pretending to be something they aren't, or an impostor. This is inferred because of the old alien movies where alien pods appear on earth and the "pod people" dispose of the humans and slowly reproduce the bodies, pretending to be humans.
The pod person was pretending to be my father, but I knew that he was an alien when he acted differently than my father ever would have.