French word autrement comes from French -ment, French autre (Another. Other.)

Detailed word origin of autrement

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.
autre	French (fra)	Another. Other.
autrement	French (fra)	Differently, in another way or manner. Otherwise.

Words with the same origin as autrement