To preside is to be the person in charge of a formal event, meeting, court, or organisation. You sit at the front, you keep order, and you have the last word on how the occasion runs. A judge presides over a trial; a chairperson presides over a meeting; someone may preside at a ceremony. You almost always preside over something — that little over matters. It is a formal verb. You would not say you preside over dinner with friends. Though actually, newspapers stretch it: a leader “presides over” a country meaning they are in charge during that time, even when they are not sitting in a meeting. And you do not have to be a president to preside. The words are cousins — both come from Latin for sitting in front — but the job title and the verb are not the same thing. English once had foresittan for this idea; preside came in from French and Latin and took its place.