'anenst' originates from Middle English, specifically the word 'anenes', where 'an' meant 'on' and 'enes' meant 'against'.

'anenes' changed from Old English 'on efen' (on even, opposite) and eventually became the modern English word 'anenst'.

Initially, it meant 'opposite to' or 'facing', but over time it evolved into its current archaic meaning of 'concerning' or 'about'.