feel on top of the world
To feel very happy. I felt on top of the world when I found out that I'd gotten an A on my hardest exam. Cathy has been feeling on top of the world ever since she got that big promotion at work.
feel on top of the world
Fig. to feel very good, as if one were ruling the world. I feel on top of the world this morning. I do not actually feel on top of the world, but I have felt worse.