What is the term for the geologic time scale unit that divides eras into smaller sections?

The term for the geologic time scale unit that divides eras into smaller sections is "Period." In geological time, periods are significant subdivisions that fall within eras, providing a more detailed framework for studying Earth's history and the evolution of life. Each period is characterized by specific geological events, changes in climate, and distinct biological developments. For instance, the Mesozoic Era is divided into three well-known periods: the Triassic, Jurassic, and Cretaceous. By using periods, geologists can better understand the timing and nature of changes occurring on Earth through millions of years. This structure enables scientists to organize Earth's history chronologically and provides crucial context for the study of geological and paleontological records.