Where does “gyrus” come from?

gyrus (Finnish) comes from Latin gȳrus, from Ancient Greek γῦρος, from Ancient Greek μίτρα, from Proto-Indo-European mey- — to strengthen; to bind; to change, exchange.

Ancestry of “gyrus”, step by step

Step	Language	Word	Meaning
1	Latin	gȳrus	circle
2	Ancient Greek	γῦρος	ring, circle
3	Ancient Greek	μίτρα	A metal guard worn round the waist; A maiden's...
4	Proto-Indo-European	mey-	to strengthen; to bind; to change, exchange

Every word from Proto-Indo-European mey- →Every word from Ancient Greek μίτρα →Every word from Ancient Greek γῦρος →