'austronesian' originates from the modern formation 'Austronesia', itself built from Latin 'auster' meaning 'south' and Greek 'nēsos' meaning 'island'; the English adjective/noun was later formed from that name.

'Austronesia' was coined in modern linguistic/geographic usage in the 19th–20th centuries to describe the 'southern islands'; the term gave rise to the English form 'austronesian' used for the language family and peoples.

Initially linked to the literal idea of 'southern islands', the term evolved to denote the language family and the peoples/cultures associated with those islands; today it primarily refers to the linguistic family and its speakers.