'Antigua' originates from Spanish, specifically the word 'antigua' (the feminine form of 'antiguo'), where 'antiguo/antigua' meant 'ancient' or 'old'. The island was named by Christopher Columbus (or early Spanish explorers) in reference to 'Santa María la Antigua' (a church in Seville) or using the adjective meaning.

'Antigua' traces back through Spanish 'antiguo/antigua' to Latin 'antiquus' meaning 'old, ancient'. The Spanish adjective was applied as a place-name (e.g., the island named 'Antigua'), and the form was carried into English as the proper name.

Initially, the root meant 'ancient' or 'old'; over time the word became used primarily as a proper name for places (the Caribbean island and the Guatemalan city) and for the nation 'Antigua and Barbuda', losing the ordinary-adjective sense in English usage.