Which term is used for a member of the same kind, class, or group?

The term "Congener" is used to describe a member of the same kind, class, or group. In various fields such as biology, chemistry, and anthropology, congeners refer to organisms or substances that are closely related and share similar characteristics because they belong to the same genus, class, or category.

For instance, in the context of biology, two species that fall under the same genus can be termed congeners, indicating a close evolutionary relationship. Similarly, in chemistry, congeners can refer to substances that have similar structural features or properties, thereby aligning them in the same broader classification.

In comparison, the other terms do not appropriately fit the definition of a member of the same kind, class, or group. "Derivative" generally refers to something that has been developed or obtained from something else, rather than being a member of the same class. "Isomer" relates specifically to compounds that have the same molecular formula but different structural arrangements, and it is more focused on molecular differences rather than relation within a class. "Analog" refers to something that is comparable or similar in some respects but does not imply membership within the same category. Thus, "congener" is the most precise term to describe a member of the same kind,