In Maya mythology, Chac (sometimes spelled "Chaac,") was the god of rain and thunder, and important as a fertility and agriculture god.
Like some other Maya gods, Chac was sometimes thought of as one god, and other times as 4 separate gods based in the four cardinal directions: "Chac Xib Chac", Red Chac of the East; "Sac Xib Chac", White North Chac; "Ek Xib Chac" Black West Chac", and "Kan Xib Chac", Yellow East Chac.
In art, he was sometimes depicted as an old man with some reptilian or amphibian features, with fangs and a long nose, sometimes tears coming from his eyes (symbolizing rain) and carrying an axe (which caused thunder). He was associated with the frog.
Other Maya terms used to refer to Chac include Ah Tzenul, ("he who gives food away to other people"), Hopop Caan ("he who lights the sky"), and Ah Hoya ("he who urinates").
Names for the Rain God in other Mesoamerican cultures include: Cocijo (Zapotec) and Tlaloc (Aztec).
While most of the ancient Mesoamerican gods are long forgotten by the descendants of the original inhabitants today, prayers to the Chaacs, especially in times of drought, are documented in Yucatan as continuing into the 20th century among otherwise Christian Maya farmers. Anthropologists have documented other prayers still in use which are identical to Pre_Columbian prayers to Chac except that the name Chac has been replaced by that of Saint Thomas.
Chac should not be confused with the Maya_Toltec figure Chac Mool.