A slang term/intentional mispronunciation used by those who grew up as hippies in the United States of America during the 60s/70s. Similar to groovy, it is used to express awe and appreciation for something exquisite, aesthetic, or tasteful.
>Receives fancy platter of well made gourmet food at a nice restaurant
>"Groovy..."
>Takes first bite
>"Excellante!"
~Quote by my grandfather, R.I.P. Papa
Radster A: "Dude, last nights episode of doing bad ass shit with bad asspeople was fucking excellent"
Radster B: "Nah dude it was excellentastic"
Radster A: "That's so true guy"