Multiloquent is an adjective used to describe someone who is known for speaking a lot or being very talkative. However, there are a few antonyms that describe the opposite of this trait. The first antonym is "reticent," which means a person who is introverted, reserved or doesn't talk much. Another antonym that can be used is "silent," which is used to describe someone who is not speaking at all. The third antonym that can be used is "taciturn," which means a person is silent or laconic by nature. So, if you're trying to describe someone who doesn't speak that much, you may want to use antonyms such as reticent, silent, or taciturn instead of multiloquent.