Where does “tribahasa” come from?

tribahasa (Indonesian) comes from Indonesian tri, from Malay tri, from Sanskrit त्रि, from Proto-Indo-Aryan tráyas, from Proto-Indo-Iranian tráyas, from Proto-Indo-European *tréyes.

tribahasa (Indonesian): trilingual

Definitions

trilingual

Ancestry of “tribahasa”, step by step

tribahasa traces back through two separate lines of ancestry.

via Indonesian tri

Step	Language	Word	Meaning
1	Indonesian	tri	three
2	Malay	tri	three
3	Sanskrit	त्रि	three
4	Proto-Indo-Aryan	tráyas	three
5	Proto-Indo-Iranian	tráyas	three
6	Proto-Indo-European	*tréyes	—

via Indonesian Bahasa

Step	Language	Word	Meaning
1	Indonesian	Bahasa	language
2	Malay	bahasa	language; decorum, appropriate social behavior
3	Sanskrit	भाषा	speech, language; any Prakrit dialect or a...
4	Sanskrit	भाष	—

Every word from Proto-Indo-European *tréyes →Every word from Proto-Indo-Iranian tráyas →Every word from Proto-Indo-Aryan tráyas →