Incite one young woman to be wasteful (8)
I believe the answer is:
prodigal
'be wasteful' is the definition.
(synonyms)
'incite one young woman' is the wordplay.
'incite' becomes 'prod' (synonyms).
'one' becomes 'i' (Roman numeral).
'young woman' becomes 'gal' (synonyms).
'prod'+'i'+'gal'='PRODIGAL'
'to' is the link.
(Other definitions for prodigal that I've seen before include "Wasteful - gold pair (anag)" , "Spendthrift" , "Wastefully extravagant" , "Grip load (anag.)" , "Recklessly wasteful or extravagant" .)