The building blocks of English

Affixes

demon(o)-

Demons.

Greek daimon, demon.

Examples include demonology, the study of demons or demonic belief; demonize or demonise, to portray someone as wicked and threatening; demonolatry (Greek ‑latria, worship), the worship of demons; demonism, belief in the power of demons; and demonomania, a form of mental disturbance in which a person believes he or she is possessed by a demon or spirit. Demonstrate is not a member of this set, as it comes instead from Latin demonstrare (de‑, entirely, plus monstrare, to show).