Definitions

1. noun

A person who talks excessively and foolishly, often about trivial matters.

“She was a notorious prattler and dominated every social gathering with her endless chatter.”

2. noun

A person who talks idly or foolishly, often about trivial matters, especially in a boastful or bragging manner.

“The self-proclaimed expert was a prattler who boasted about his non-existent accomplishments.”