Where does “-ide” come from?

-ide (Italian) comes from Latin -is, from Latin -a, from Proto-Italic -ā, from Proto-Indo-European -éh₂.

-ide (Italian): id (dynast)

Definitions

Step	Language	Word	Meaning
1	Latin	-is	suffixed to the root of nouns in composition,...
2	Latin	-a	suffixed to the roots of verbs, forms agent...
3	Proto-Italic	-ā	Forms masculine agent nouns from prefixed or compounded bases
4	Proto-Indo-European	-éh₂	—