declivity

The story

1. Proto-Indo-European · derived from*ḱley-“to lean”
2. Proto-Indo-European · derived from*ḱleywo-
3. Latin · derived fromdeclivitatem
4. French · derived fromdéclivité
5. English todaydeclivity

1610s, from French déclivité, from Latin declivitatem, dēclīvitās, from dēclivis (“a sloping downward”), from de (“down”) + clīvus (“a slope”), from Proto-Indo-European *ḱleywo-, from Proto-Indo-European *ḱley- (“to lean”) (English lean).

Words from the same roots