Familiarities are the things that we know well and are accustomed to. The antonyms of unfamiliarities are the terms, concepts, and situations that are known to us. They include the familiar, well-known, routine, customary, habitual and usual, among others. The opposite of unfamiliarities is also the known, the recognized, the understood, and the common. The familiarities are the things that we take for granted, and we do not need to put in any effort to understand them. On the other hand, the unfamiliarities are the things that require our attention and effort to get acquainted with. Therefore, understanding the antonyms of unfamiliarities can help us gain a better understanding of the world around us, and we can adapt to new situations and environments.