Where does “silta-arkku” come from?

silta-arkku (Finnish) comes from Finnish arkku, from Proto-Norse ᚨᚱᚲᚢ, from Latin arca, from Latin arceo, from Proto-Italic arkeō, from Proto-Indo-European h₂erk- — to protect, guard, hold, lock.

silta-arkku (Finnish): bridge support; a structure, especially a wide or broad one, on the ground that supports a bridge

Definitions

bridge support; a structure, especially a wide or broad one, on the ground that supports a bridge

Ancestry of “silta-arkku”, step by step

silta-arkku traces back through two separate lines of ancestry.

via Finnish arkku

Step	Language	Word	Meaning
1	Finnish	arkku	chest; trunk; coffin
2	Proto-Norse	ᚨᚱᚲᚢ	—
3	Latin	arca	chest, box, coffer, safe; coffin; ark
4	Latin	arceo	I shut up, enclose; box in; I keep off, ward off;...
5	Proto-Italic	arkeō	to contain
6	Proto-Indo-European	h₂erk-	to protect, guard, hold, lock

via Finnish siltä

Step	Language	Word	Meaning
1	Finnish	siltä	Ablative singular form of se
2	Finnish	-lä	Front vowel variant of -la
3	Finnish	-as	Forms some adjectives; Forms some nouns
4	Proto-Finnic	-s	Forms nouns
5	Proto-Finno-Ugric	-s	—

Every word from Proto-Indo-European h₂erk- →