Where does “déclinaison” come from?
déclinaison (French) comes from Middle French declinaison, from Latin dēclīnātiō, from Latin -ātiō, from Latin -tiō, from Latin dissertātiō, from Latin dissertus, from Latin disserere, from Latin dis- — small stone, pebble; gravel, rubble.
déclinaison (French): declension; declination
Ancestry of “déclinaison”, step by step