In climatology, the term megathermal (or less commonly, macrothermal) is sometimes used as a synonym for "tropical." The word megathermal is derived from two Greek words meaning "having great heat." In order for a particular place to qualify as having a megathermal climate, every single month out of the year must have an average temperature of 18°C or above. Megathermal climates are sometimes split into two temperature-based subsets — equatorial and tropical (the latter used here in t… (More on Megathermal)