Loudmouth baronet trapping fish with bait (8)
I believe the answer is:
braggart
'loudmouth' is the definition.
(thesaurus)
'baronet trapping fish with bait' is the wordplay.
'baronet' becomes 'bt'.
'trapping' indicates putting letters inside.
'fish' becomes 'gar' (type of fish).
'with' means one lot of letters go next to another.
'bait' becomes 'rag' (synonyms).
'gar' after 'rag' is 'raggar'.
'bt' going around 'raggar' is 'BRAGGART'.
(Other definitions for braggart that I've seen before include "Big noter" , "Big boaster" , "bigmouth" , "Show-off" , "Boastful type" .)