Medithermal
/ˌmiːdɪˈθəːml/Ecology and Archaeol.
adjective
Designating or relating to the most recent climatic phase in the Holocene of North America, following the Altithermal phase (from about 2500 b.c.) and characterized by a gradually cooling climate in central and western regions.
Origin
1940s. From medi- + thermal. Compare Anathermal and Altithermal.