Loud aggressive talk (7)
I believe the answer is:
bluster
'loud aggressive talk' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for bluster that I've seen before include "Empty boasting" , "Swagger" , "Swaggering language" , "Talk aggressively to little or no effect" , "Boastful and bullying talk" .)