One of the mysteries of the English language finally explained.
Definition of prophetize in US English:
prophetize
(also prophetise)
verb
1with object To prophesy or predict (a future event or situation).
2no object To make or utter a prediction; to prophesy.
Origin
Late Middle English; earliest use found in Robert Mannyng (d. c1338), poet and historian. From Anglo-Norman prophetizer and Middle French prophetiser (French prophétiser) to prophesy, to prophesy or predict (a future event or situation) and its etymon post-classical Latin prophetizare to prophesy, predict (Vetus Latina, Vulgate), perhaps from ancient Greek προϕητίζειν to prophesy (although this is only recorded in an isolated attestation in Hippocrates: see note below) from προϕήτης + -ίζειν. Compare Old Occitan profetizar, Catalan profetitzar, Spanish profetizar, Portuguese profetizar, Italian profetizzare.