Where does “torn” come from?

torn (Old High German) comes from Latin Turris, from Ancient Greek τύρρις, from Ancient Greek τύρσις — tower, bastion.

Ancestry of “torn”, step by step

Step	Language	Word	Meaning
1	Latin	Turris	A river of Venetia, now called Torre
2	Ancient Greek	τύρρις	tower, walled city
3	Ancient Greek	τύρσις	tower, bastion