High spirits, vitality (3)
I believe the answer is:
pep
I believe this clue is a double definition.
'high spirits' is the first definition.
(both can mean enthusiasm or energy)
'vitality' is the second definition.
(I've seen this in another clue)
(Other definitions for pep that I've seen before include "Get-up-and-go" , "Energy, zip" , "Palindrome for vitality or energy" , "Energy or enthusiasm" , "Palindrome for vigour" .)