From April, dog becomes wasteful (8)
I believe the answer is:
prodigal
'wasteful' is the definition.
(synonyms)
'from april dog' is the wordplay.
'from' is an anagram indicator (from the letters).
'april'+'dog'='aprildog'
'aprildog' is an anagram of 'PRODIGAL'.
'becomes' is the link.
(Other definitions for prodigal that I've seen before include "Extravagant - lavish" , "Wastefully extravagant" , "Wasting money" , "overspending" , "reckless" .)