Where does “tridiapason” come from?

tridiapason (English) comes from English diapason, from Latin diapason, from Ancient Greek διαπασῶν, from Ancient Greek διά, from Proto-Indo-European dwís, from Proto-Indo-European dwóh₁ — two.

tridiapason (English): A triple octave, or twenty-second

Definitions

A triple octave, or twenty-second

Ancestry of “tridiapason”, step by step

tridiapason traces back through two separate lines of ancestry.

via English diapason

Step	Language	Word	Meaning
1	English	diapason	The musical octave; The range or scope of...
2	Latin	diapason	—
3	Ancient Greek	διαπασῶν	octave
4	Ancient Greek	διά	throughout
5	Proto-Indo-European	dwís	twice, doubly; in two
6	Proto-Indo-European	dwóh₁	two

via English tri

Step	Language	Word	Meaning
1	English	tri	triathlon; triangle
2	Proto-Indo-European	tréyes	three

Every word from Proto-Indo-European dwóh₁ →Every word from Proto-Indo-European dwís →Every word from Ancient Greek διά →