Well, I really don't think that's the case with most of the Carnival ships. But it likely holds true for some. Those would be the ships who have the same names as other ships belonging to other cruise lines. Spirit, Legend, Pride all probably are noted with Carnival coming before their names just to differentiate them from other lines.
While, I think the "ation" ships are simply referred to as Imagination, Fascination, Sensation, etc. As I think that's true of Destiny, Triumph, Conquest, and the upcoming Miracle, as well.