Where does “দ্বিতীয়” come from?

দ্বিতীয় (Assamese) comes from Sanskrit द्वितीय, from Proto-Indo-Aryan dwitíyas, from Proto-Indo-Iranian dwitíyas, from Proto-Indo-European dwitíyos, from Proto-Indo-European dwi-, from Proto-Indo-European dwóh₁ — two.

দ্বিতীয় (Assamese): second

Definitions

second

Ancestry of “দ্বিতীয়”, step by step

Step	Language	Word	Meaning
1	Sanskrit	द्वितीय	second, second part, second half; fellow; second...
2	Proto-Indo-Aryan	dwitíyas	—
3	Proto-Indo-Iranian	dwitíyas	second
4	Proto-Indo-European	dwitíyos	—
5	Proto-Indo-European	dwi-	two; apart, asunder
6	Proto-Indo-European	dwóh₁	two

Every word from Proto-Indo-European dwóh₁ →Every word from Proto-Indo-European dwi- →Every word from Proto-Indo-European dwitíyos →