- climate
- late 14c., from O.Fr. climat, from L. clima (gen. climatis) "region, slope of the Earth," from Gk. klima "region, zone," from base of klinein "to slope," thus "slope of the Earth from equator to pole," from PIE base *klei- "to lean" (see lean (v.)). Angle of sun on the slope defined the zones assigned by early geographers. Meaning moved from "region" to "weather associated with that region" by c.1600.