It's a more formal way of saying someone is chatty or garrulous.
Here are some synonyms:
* Talkative
* Chatty
* Garrulous
* Voluble
* Fluent
* Effusive
* Rambling
* Prolix
Here are some examples of how to use "loquacious" in a sentence:
* "The loquacious bartender regaled us with stories of his travels."
* "She was a very loquacious woman, always ready with a story or opinion."
* "The meeting was dominated by the loquacious CEO."