<p><strong>Adjective</strong></p><ul><li>of, relating to, or characterized by ceremony; formal; ritual: a ceremonial occasion.</li><li>Synonyms: ceremonious, conventional, solemn.</li><li>Antonyms: informal.</li><li>used in or in connection with ceremonies: ceremonial robes.</li></ul><p><strong>Noun</strong></p><ul><li>a system of ceremonies, rites, or formalities prescribed for or observed on any particular occasion; a rite.</li><li>Synonyms: liturgy, ritual.</li><li>Roman Catholic Church: the order for rites and ceremonies.</li><li>a book containing it.</li><li>formal behavior found at, or appropriate to, a certain occasion: the ceremonial of a state banquet.</li></ul>