Commensalis

Commensalis (plural commensales) is a Latin noun meaning a person who shares a table; etymology derives from com- meaning together and mensa meaning table. In Roman society, commensales were individuals who formed networks of social obligation and reciprocity through shared meals, often within the framework of patronage and hospitality.

In anthropology and sociology, commensality refers to the practice of eating together as a social act that helps regulate relationships, status, and identity. Meals within households, at feasts, or during ritual gatherings can encode hierarchy, obligation, and solidarity. The study of commensality explores how sharing food shapes kinship, reciprocity, generosity, and power across cultures and social groups.

In biology, the term commensalis (also commensalist) or commensal is used to describe an organism that benefits from association with another organism without harming it; this relationship is called commensalism. Examples include certain epibionts on larger animals or bacteria that reside on skin or mucous surfaces. The host is typically considered unaffected, while the commensal gains nutrients, habitat, or dispersal opportunities. In practice, the neutrality of commensal relationships is frequently debated, and many interactions may have subtle effects on one or both partners.

In modern usage, commensalis is more common in older texts or Latin dictionaries; in English, commensal or commensalist is preferred for describing either the human social role or the ecological partner, respectively. The concept of commensality remains influential in cultural anthropology, sociology, and ecology.