'attenuative' originates from Latin, specifically from 'attenuare' (to make thin), where 'ad-' meant 'to, toward' (assimilated to 'at-') and 'tenuare' derived from 'tenuis' meant 'thin'.

'attenuare' passed into Late Latin and then into Middle French/Medieval Latin influences and Middle English as forms like 'attenuaten' before developing into the modern English adjective 'attenuative'.

Initially, the root meant 'to make thin' or 'make less dense'; over time the sense broadened to the general idea of reducing strength, intensity, or effect, which is the modern usage.