Where does “Marcos” come from?

Marcos (Old Portuguese) comes from Latin Marcus, from Latin Mars, from Latin Mavors, from Proto-Italic Māwortis.

Ancestry of “Marcos”, step by step

Step	Language	Word	Meaning
1	Latin	Marcus	—
2	Latin	Mars	war, battle, conflict
3	Latin	Mavors	—
4	Proto-Italic	Māwortis	—

Marcos — Etymology, Origin & Word History | Etymology Explorer