'antilogarithm' originates from Greek elements via New Latin/Modern English, specifically from the prefix 'anti-' and the word 'logarithm' (from Greek 'logarithmos'), where 'anti-' meant 'against' or 'opposite' and 'logarithmos' meant 'ratio' or 'number'.

'antilogarithm' was formed from New Latin/early modern forms combining 'anti-' + 'logarithm' (e.g. New Latin/early scientific usage such as 'antilogarithmus') and eventually became the modern English word 'antilogarithm'.

Initially it meant 'the inverse of a logarithm', and over time this technical mathematical meaning has remained essentially the same.