Full of excitement (4)
I believe the answer is:
agog
'full of excitement' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for agog that I've seen before include "Wide-eyed and fascinated" , "Very eager (in anticipation)" , "on the edge of your seat" , "Eager and wide-eyed" , "Open-mouthed" .)