Where does “Senin” come from?

Senin (Malay) comes from Classical Malay اثنين, from Arabic الاِثْنَيْن, from Arabic اِثْنَان — two.

Senin (Malay): Monday

Definitions

Step	Language	Word	Meaning
1	Classical Malay	اثنين	—
2	Arabic	الاِثْنَيْن	—
3	Arabic	اِثْنَان	two

Senin — Etymology, Origin & Word History | Etymology Explorer