molybdomancy
divination by interpreting shapes formed when molten metal, typically lead or tin, is dropped into water.
uncountable
MOLUBDOMANCY [molybdomanteia of molybdos Lead, and manteia Divination, Gr.] a divining, an observing the motions, Figures, &c. of melted Lead.
1727, Bailey, The Universal Etym. Eng. Dict.
Where it comes from
From Ancient Greek μόλυβδος (mólubdos, “lead”) and the suffix -mancy. Probably after Greek μολυβδομαντεία (molyvdomanteía) or French molybdomancie.
Adapted from the Wiktionary entry molybdomancy (CC BY-SA 4.0).