Which term describes blood relatives through both male and female lines?

The term that describes blood relatives through both male and female lines is "cognati." This term comes from Latin, meaning "those who are related through blood" and refers to individuals who are connected by family ties regardless of whether those connections are through the paternal or maternal lineage.

This concept is significant in various legal and social contexts, especially in Rome, where family relations played a crucial role in inheritance rights and social standing. Cognati would include siblings, cousins, and other relatives who descend from either parent, emphasizing the inclusive nature of familial relationships that encompass both sides of the family.

Other terms in the choices refer to more specific relationships. For instance, "agnati" pertains specifically to blood relatives through the male line, focusing on paternal connections. "Adfines" refers to relatives by marriage, and "consanguinei" relates to those who are related by blood, but often in more technical or restricted terms compared to cognati. Thus, cognati is the comprehensive term used for all blood relatives through both male and female lines.