blatherer
/ˈblæθərər/Definitions
1. noun
A person who talks excessively and foolishly, often about trivial matters.
“The politician’s reputation as a blatherer was damaged by her recent speech.”
2. noun
A person who talks at length, often about something of little importance, but in a way that is tedious and boring.
“After listening to the blatherer for hours, I had to excuse myself from the party.”