Latin word -um comes from Proto-Celtic *wēros (Crooked.), Spanish diphthong

Detailed word origin of -um

Dictionary entry	Language	Definition
*wēros	Proto-Celtic (cel-pro)	Crooked.
diphthong	Spanish (spa)
viria	Latin (lat)	Sort of bracelet worn by men.
viriola	Latin (lat)
virole	Old French (fro)
ferrum	Latin (lat)	Any tool made of iron. Iron. Sword.