The crossword solution for the term 'Antiquity, Once' is ELD. This acronym stands for 'Era of Late Antiquity, ' which is a period of time in the history of the Mediterranean world that began in the 4th century and lasted until the 7th century. During this time, the Roman Empire was in decline and the Byzantine Empire was emerging. This period saw the rise of Christianity and the fall of paganism, as well as the spread of Islam.