Final answer:
The first word in 'Homo sapiens' refers to the genus 'Homo'. The genus is part of the biological classification system and indicates the group of closely related species. In our case, the genus Homo has had multiple species, but only Homo sapiens currently exists.
Step-by-step explanation:
The first word in our species name, Homo sapiens, refers to the genus to which we belong. The biological classification system orders life into a hierarchy of categories, and genus is one such category. In the naming convention known as binomial nomenclature, the first word of a species' scientific name denotes its genus while the second indicates the species itself. So, in Homo sapiens, Homo identifies the genus that includes modern humans and our close extinct relatives.
Our genus, Homo, is within the hominid family, which is part of the primate order, within the mammal class, in the chordate phylum of the animal kingdom, and belongs to the domain Eukarya. The genus Homo first evolved approximately 2.8 million years ago, and though it has been represented by multiple species throughout history, only Homo sapiens has survived to the present day.