To compose or sing an epithalamium, which is a song or poem celebrating a wedding.
From Greek epi- (upon) + thalamos (bridal chamber) + -ize (to make or do). The term emerged in ancient Greek poetry as a specific literary form for wedding celebrations, with the -ize suffix added in modern usage to create a verb form.
Ancient Greek poets had such a strong tradition of wedding songs that they created an entire vocabulary just for celebrating marriages—epithalamiums were literally performed at real weddings to bless the newlyweds' first night together in their chamber.
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