French word affreusement comes from French -ment, French affreuse

Detailed word origin of affreusement

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.
affreuse	French (fra)
affreusement	French (fra)	Dreadfully (in a dreadful manner), horribly.

Words with the same origin as affreusement