Causeries are light and informal conversations that are usually held among friends, and they often revolve around everyday topics like food, fashion, movies, and culture. As such, a few antonyms that could describe the opposite of causeries might include formal conversations, serious discussions or debates, business meetings, or academic lectures. Causeries are often characterized by their lighthearted and playful tone, so any words that evoke a sense of solemnity or gravity would be suitable antonyms for this word. Additionally, antonyms for causeries might include terms that describe social isolation, like loneliness or isolation, as causeries tend to be social events that are enjoyed in the company of others.