The word "triplicities" refers to a grouping of three things, and there are many synonyms that can be used to describe this concept. One common synonym is "triad," which suggests a group of three entities that are interconnected or interdependent in some way. Other synonyms for "triplicities" include "trilogy," "triumvirate," "trinity," "troika," and "triune." Each of these options conveys a slightly different shade of meaning, such as a set of three related novels, a ruling body composed of three individuals, or a religious concept of a unified, three-part divine nature. Ultimately, the choice of synonym will depend on the context in which it is being used.