Humour’s eluding oddball (7)
I believe the answer is:
indulge
'humour's' is the definition.
(I've seen this before)
'eluding oddball' is the wordplay.
'oddball' indicates anagramming the letters.
'eluding' is an anagram of 'INDULGE'.
(Other definitions for indulge that I've seen before include "Pamper, spoil" , "Drink too much" , "Enjoy to excess" , "Allow person to have what he/she wishes" , "Gratify, spoil" .)