Big talkers blasted band wearing hairpieces (8)
I believe the answer is:
windbags
'big talkers' is the definition.
(both can mean overly talkative people)
'blasted band wearing hairpieces' is the wordplay.
'blasted' is an anagram indicator.
'wearing' means one lot of letters goes inside another.
'hairpieces' becomes 'wigs' (wig is a kind of hairpiece).
'band' anagrammed gives 'ndba'.
'ndba' placed inside 'wigs' is 'WINDBAGS'.
(Other definitions for windbags that I've seen before include "Blusterers" , "They're boring and they talk a lot" .)