Where does “oranssirousku” come from?

oranssirousku (Finnish) comes from Finnish oranssi, from Swedish orange, from French Orange, from Spanish naranja, from Old Spanish naranja, from Arabic نَارَنْج, from Persian نارنگ, from Sanskrit नारङ्ग — date palm.

oranssirousku (Finnish): A milk-cap, "Lactarius mitissimus"

Definitions

A milk-cap, "Lactarius mitissimus"

Ancestry of “oranssirousku”, step by step

oranssirousku traces back through two separate lines of ancestry.

via Finnish oranssi

Step	Language	Word	Meaning
1	Finnish	oranssi	orange; color orange
2	Swedish	orange	orange (orange-coloured)
3	French	Orange	Orange
4	Spanish	naranja	orange; Pertaining to Ciudadanos, a Spanish...
5	Old Spanish	naranja	orange
6	Arabic	نَارَنْج	bitter orange
7	Persian	نارنگ	bitter orange
8	Sanskrit	नारङ्ग	the orange-tree; the juice of the pepper plant;...
9	Dravidian	dra	—
10	Proto-Dravidian	*cīntu	date palm

via Finnish rousku

Step	Language	Word	Meaning
1	Finnish	rousku	A milk-cap
2	Finnish	-u	Forms nouns from verbs. Most common with "e"- and...
3	Proto-Finnic	-u	Forms nouns from adjectives, nouns

Every word from Proto-Dravidian *cīntu →Every word from Dravidian dra →Every word from Sanskrit नारङ्ग →