'austrine' originates from Latin, specifically from 'austrinus' (from 'Auster'), where 'Auster' meant 'south' or the 'south wind'.

'austrine' passed into English via Late/Medieval Latin 'austrinus' (and related forms such as 'australis'), and was formed in English on the model of Latin-derived adjectives meaning 'of the south'.

Initially it meant 'of or pertaining to the south' (often literally 'of the south wind'), and over time it has retained this core meaning as 'relating to the south' in modern usage.