Where does “Iiro” come from?

Iiro (Finnish) comes from Finnish Iisakki, from Finnish Iisak, from Swedish Isak, from Ancient Greek Ἰσαάκ, from Hebrew יצחק — to laugh.

Ancestry of “Iiro”, step by step

Step	Language	Word	Meaning
1	Finnish	Iisakki	Isaac
2	Finnish	Iisak	Isaac's; Isaac
3	Swedish	Isak	—
4	Ancient Greek	Ἰσαάκ	—
5	Hebrew	יצחק	to laugh