Where does “Khorasan” come from?

Khorasan comes from Middle Persian hwlʾsʾn', which developed into Persian خوراسان and خراسان, referring to a historical region in Central Asia.

Ancestry of “Khorasan”, step by step

Step	Language	Word	Meaning
1	Persian	خراسان	Khorasan
2	Persian	خوراسان	—
3	Middle Persian	hwlʾsʾn'	—

Khorasan — Etymology, Origin & Word History | Etymology Explorer