Where does “sini” come from?

sini (Latin) comes from Latin sino, from Proto-Indo-European si-n-H-, from Proto-Indo-European sey(H)- — to put.

sini (Latin): present passive infinitive of sinō

Definitions

Step	Language	Word	Meaning
1	Latin	sino	I let, permit, allow, suffer; I put, lay, set...
2	Proto-Indo-European	si-n-H-	—
3	Proto-Indo-European	sey(H)-	to put

sini — Etymology, Origin & Word History | Etymology Explorer