'apotropic' originates from Greek, specifically the word 'apotrópē' (from the verb 'apotropein'), where 'apo-' meant 'away from' and 'trepein' (or the root 'trop-') meant 'to turn'.

'apotropic' passed into Late/Medieval Latin as 'apotropaeus' and via later scholarly/vernacular use gave English forms such as 'apotropic' and the related 'apotropaic'.

Initially it meant 'turning away' (literally 'turning away something harmful'); over time it came to be used specifically of things believed to 'ward off evil' or harmful influences.