Where does “mersì” come from?

mersì (Italian) comes from French merci, from Middle French merci, from Old French merci, from Latin mercēs, from Latin merx, from Proto-Italic *merks.

mersì (Italian): thanks! thank you!

Definitions

thanks! thank you!

Ancestry of “mersì”, step by step

Step	Language	Word	Meaning
1	French	merci	thank you; mercy, grace
2	Middle French	merci	—
3	Old French	merci	mercy; clemency
4	Latin	mercēs	pay, wages, reward
5	Latin	merx	merchandise, commodity; goods, wares
6	Proto-Italic	*merks	—

Every word from Proto-Italic *merks →Every word from Latin merx →Every word from Latin mercēs →