A holy day is a day that is considered sacred or religiously significant. There are various synonyms for this term, such as feast day, festival, or commemoration day. These terms are used to refer to special days that are set aside for religious observance or celebration. A feast day usually refers to such a day in the context of Christian worship. A festival is a term that can apply to any religious or cultural event, while a commemoration day is usually used to remember a specific person or event in religious history. Other synonyms for a holy day include Sabbath, rest day, and day of worship.