'occlusive' originates from Latin, specifically the Late Latin/Medieval Latin word 'occlusivus', where 'oc-' (a variant of 'ob-') meant 'against/toward' and 'claudere' (from which 'clus-' derives) meant 'to shut/close'.

'occlusivus' in Late Latin passed into Medieval Latin and Old French (e.g. 'occlusif') and eventually entered English as 'occlusive' via learned borrowings.

Initially, it meant 'tending to close or shut', and over time it retained that central sense while being specialized for medical, physical, and phonetic uses as 'causing blockage' or 'relating to occlusion'.