A person who practices divination; one who attempts to divine or predict future events through supernatural means.
From Latin 'divinare' plus the agent suffix '-er' (one who does something), possibly influenced by French -iste variants.
The term 'divinister' is extremely rare in English, but it shows how the same root word spawns different occupational titles across languages and time periods.
Complete word intelligence in one call. Free tier — 50 lookups/day.