Where does “Tir” come from?

Tir comes from Persian تیر, from Middle Persian 𐭧𐭲𐭩𐭠, with the original meaning now obscure.

Ancestry of “Tir”, step by step

Step	Language	Word	Meaning
1	Persian	تیر	arrow; bullet; dart
2	Old English	tīr	glory, honour, fame; fame, glory, honor
3	Proto-Germanic	tīraz	—
4	Proto-Indo-European	dey-	to shine; to gleam, shimmer, shine; to swing, to...

Tir — Etymology, Origin & Word History | Etymology Explorer