somebody who talks a lot
loquacious - talkative
If a person is ‘loquacious’, then they are very talkative, usually only about things that they find interesting. The word is also used in relation to somebody who is a highly capable and articulate speaker.
John is very loquacious, so he ends up dominating every meeting as no one else can get a word in edgeways!
The lawyer’s loquaciousness has been a big factor in her excellent acquittal record.
Kevin spoke loquaciously to the interviewer about his ambitions and motivations.