'Antilia' originates from medieval Portuguese/Latin usage, specifically the form 'Antillia' or 'Antília,' where elements like 'ante' (before/opposite) and Portuguese 'ilha' (island) are thought to be components of the name.

'Antilia' changed from the medieval cartographic name 'Antillia' (used on 15th-century portolan charts) and later influenced the naming of the Caribbean 'Antilles'; in modern times the term has also been adopted as a proper name (for example, the Mumbai residence 'Antilia').

Initially, it referred to a legendary or phantom island on early maps; over time the form was applied to real geographic naming (the Antilles) and later reused as a modern proper name for buildings and other entities.