Most boisterous wife longs to break mould (8)
I believe the answer is:
rowdiest
'most boisterous' is the definition.
(I've seen this before)
'wife longs to break mould' is the wordplay.
'wife' becomes 'w'.
'longs' becomes 'dies' (to be dying for something is to long for it).
'to break' indicates putting letters inside.
'mould' becomes 'rot' (I can't justify this - if you can you should believe this answer much more).
'w'+'dies'='wdies'
'wdies' inserted into 'rot' is 'ROWDIEST'.
Can you help me to learn more?
(Other definitions for rowdiest that I've seen before include "Most noisy and disorderly" , "Most boisterous" .)