The most common and most likely answer to this crossword clue is the 2 plus 3 plus 2 plus 3 plus 5 letter word ON TOP OF THE WORLD
I've seen this crossword clue in The Sunday Telegraph
O
N
T
O
P
O
F
T
H
E
W
O
R
L
D
More clues leading to the result ON TOP OF THE WORLD
- Happy as a successful North Pole expedition?
- A great place for polar bears?
- Feeling extremely happy, having reached the North Pole?
- Happy as a polar bear, but not as a penguin?
- Very happy — as Robert Peary may have been in 1909?
- Elated, having reached the North Pole?
- Happy as Ma Jarrett’s boy meeting his fate?
- Delighted to be at planetary summit
- Delighted when told foot op cast will wrap up right
- Sitting pretty with pot noodle for stirring. Not I!
Buddy explains!
The straight part
We know that "Very happy" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case very happy = on top of the world.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.