ceremony
n. C / Un. a formal event that people hold to celebrate a special occasion, like a wedding or a graduation. It usually involves traditional actions or speeches.
n. a formal religious or public occasion, typically one celebrating a particular event or anniversary. It often follows a prescribed set of rituals or traditional procedures.
The wedding ceremony starts at two o'clock.
The university holds a graduation ceremony every summer to honor the students who finished their degrees.
The coronation was a grand ceremony steeped in centuries of tradition, designed to reinforce the continuity of the state through symbolic gestures and ancient oaths.
From Middle English cerymonye, from Latin caerimonia or caeremonia, later often cerimonia (“sacredness, reverence, a sacred rite”).
Countable when referring to specific events; uncountable when referring to formal behavior or ritual in general ('performed with great ceremony').