Where does “фтор” come from?

фтор (Mongolian) comes from Russian фтор, from French phthore, from Ancient Greek φθορά, from Ancient Greek φθείρω, from Proto-Hellenic kʷʰtʰéřřō, from Proto-Indo-European dʰgʷʰér-ye-ti, from Proto-Indo-European dʰgʷʰer- — flow, diverge; perish.

фтор (Mongolian): fluorine

Definitions

fluorine

Ancestry of “фтор”, step by step

Step	Language	Word	Meaning
1	Russian	фтор	fluorine
2	French	phthore	—
3	Ancient Greek	φθορά	destruction, ruin; passing out of existence,...
4	Ancient Greek	φθείρω	I destroy; I ruin, spoil
5	Proto-Hellenic	kʷʰtʰéřřō	—
6	Proto-Indo-European	dʰgʷʰér-ye-ti	—
7	Proto-Indo-European	dʰgʷʰer-	flow, diverge; perish

Every word from Proto-Indo-European dʰgʷʰer- →Every word from Proto-Indo-European dʰgʷʰér-ye-ti →Every word from Proto-Hellenic kʷʰtʰéřřō →