What is the term for the main meal of the day in Roman times?

The main meal of the day in Roman times is referred to as "cena." This meal typically occurred in the late afternoon or evening and was the most substantial and important meal for Romans. It was during cena that families would gather, often enjoying multiple courses, and it played a significant role in social rituals and relationships.

In contrast, the other terms refer to different aspects of Roman dining culture. "Gustatio" refers to a starter or appetizer course—a lighter beginning to the meal. "Vesperna" was a lighter evening meal, usually taken after cena. "Glis" is the Latin term for dormouse, which was considered a delicacy, but is not a term used to define a meal. These distinctions illustrate the importance of cenation in the social and cultural fabric of Roman life.