Where does “-umen” come from?

-umen (Latin) comes from Latin -men, from Proto-Italic *-mn̥.

Ancestry of “-umen”, step by step

Step	Language	Word	Meaning
1	Latin	-men	forms neuter nouns of the third declension
2	Proto-Italic	*-mn̥	—

-umen — Etymology, Origin & Word History | Etymology Explorer