Upkeep oddly absent — energy found (3)
I believe the answer is:
pep
'absent energy found' is the definition.
I can't tell whether this definition defines the answer.
'upkeep oddly' is the wordplay.
'oddly' indicates alternate letters (letters in odd-numbered positions).
The alternating letters of 'upkeep' are 'PEP'.
Can you help me to learn more?
(Other definitions for pep that I've seen before include "Energy, liveliness" , "Vim and vitality" , "Palindromic energy or vim" , "Energy or enthusiasm" , "Palindrome for vitality or energy" .)