'altar-cover' originates from English, specifically the words 'altar' and 'cover', where 'altar' ultimately comes from Latin 'altare' meaning 'high place, altar' and 'cover' comes via Old French/Old North French 'coverer' (from Latin 'cooperire') meaning 'to cover'.

'altar' entered English from Church Latin 'altare' (and via Old French influence) meaning 'high place' or 'altar'; 'cover' arose from Old French/Old North French 'coverer' (from Latin 'cooperire'); the compound 'altar-cover' developed in Modern English as a descriptive compound for a covering used on an altar.

Initially, 'altar' meant 'high place' and 'cover' meant 'to cover'; combined as 'altar-cover' the meaning has remained the literal 'cloth that covers an altar' with little semantic shift.