'annam' (the regional name) originates from Sino-Vietnamese 'An Nam' (Chinese characters '安南'), where '安' meant 'peace' or 'pacified' and '南' meant 'south'. The French form 'Annam' was adopted during colonial administration.

'An Nam' (Sino-Vietnamese) was used in medieval and later Vietnamese contexts; through contact with Chinese and later French transliteration it became the modern Western form 'Annam' referring to the central Vietnamese protectorate.

Initially it literally meant 'pacified south' (安 = pacified/peace, 南 = south) as a political/geographic designation; over time it became the standard external name for the central Vietnamese region and the colonial protectorate 'Annam'.