Silly talk (7)
(Other definitions for twaddle that I've seen before include "Hot air" , "Bull" , "Foolish speech" , "Claptrap" , "Rubbish" .)
(Other definitions for blather that I've seen before include "Long-winded talk with no substance" , "Talk ramblingly" , "Palaver, prattle" , "Long-winded talk making little sense" , "Foolish chatter, just oul' talk" .)