French word prouvablement comes from French -ment, French prouvable (Provable. Verifiable.)

Detailed word origin of prouvablement

Dictionary entry	Language	Definition
-ment	French (fra)	Used to form adverbs (from the feminine form of an adjective), most of the time equivalent to the English -wise, -ly. Used to form nouns from verbs, usually of action or state resulting of them. Equivalent to the English -ment.
prouvable	French (fra)	Provable. Verifiable.
prouvablement	French (fra)	Provably. Verifiably.

Words with the same origin as prouvablement