loquaciousness

/loʊˈkweɪʃəsnəs/
noun
  1. The quality of being very talkative; talkativeness.
    • His loquaciousness sometimes annoyed his quiet coworkers.
    • The teacher appreciated the student's loquaciousness during class discussions.
    • Her loquaciousness made her a popular guest at social events.
Antonyms