Where does “raison” come from?

raison (French) comes from Old French reson, from Latin ratiō, from Latin -tiō, from Latin dissertātiō, from Latin dissertus, from Latin disserere, from Latin dis-, from Latin calceus — small stone, pebble; gravel, rubble.

raison (French): reason; common difference; common ratio

Definitions

reason; common difference; common ratio

Ancestry of “raison”, step by step

Step	Language	Word	Meaning
1	Old French	reson	logic, logical reasoning
2	Latin	ratiō	reason, reasoning, explanation, ground, motive, rationality, rationale, purpose
3	Latin	-tiō	tion, -ation, -ing
4	Latin	dissertātiō	(spoken) dissertation, discourse, disquisition
5	Latin	dissertus	arranged, disposed; explained
6	Latin	disserere	second-person singular future passive indicative...
7	Latin	dis-	asunder, apart, in two; reversal, removal;...
8	Latin	calceus	shoe
9	Latin	calx	limestone; chalk; the finish line
10	Ancient Greek	χάλιξ	small stone, pebble; gravel, rubble

Words derived from “raison”

Every word from Ancient Greek χάλιξ →Every word from Latin -tiō →Every word from Latin dis- →