Where does “sināpis” come from?

sināpis (Latin) comes from Ancient Greek σίναπι, from Demotic snwpt.

Ancestry of “sināpis”, step by step

Step	Language	Word	Meaning
1	Ancient Greek	σίναπι	the mustard plant
2	Demotic	snwpt	—

sināpis — Etymology, Origin & Word History | Etymology Explorer