Smashing spindle damaged daughter (8)
I believe the answer is:
splendid
'smashing' is the definition.
(thesaurus)
'spindle damaged daughter' is the wordplay.
'damaged' is an anagram indicator.
'daughter' becomes 'd' (genealogical abbreviation).
'spindle' with letters rearranged gives 'splendi'.
'splendi'+'d'='SPLENDID'
(Other definitions for splendid that I've seen before include "Characterised by grandeur" , "super" , "Grand" , "Very fine, glorious" , "Excellent, magnificent" .)