Loquacious type (9)
(Other definitions for loudmouth that I've seen before include "Pistol, for example" , "boastful type?" , "Braggart" , "Blowhard" , "noisy type" .)
(Other definitions for chatterbox that I've seen before include "One using plenty of gas" , "who rabbits on?" , "Windbag" , "Babbler" , "Bletherer" .)