Nicer pet name could give one licence (12)
I believe the answer is:
intemperance
'one licence' is the definition.
(intemperance means license or lack of restraint)
'nicer pet name could' is the wordplay.
'nicer pet name' anagrams to 'INTEMPERANCE'.
Though, I'm not clear how the anagram is indicated.
'give' is the link.
Can you help me to learn more?
(Other definitions for intemperance that I've seen before include "lack of restraint" , "bingeing" , "Unrestrained alcohol consumption" , "excess drunkenness?" .)