Where does “litre” come from?

litre (French) comes from Medieval Latin litra, from Ancient Greek λίτρα, from Proto-Italic *līðrā.

litre (French): litre

Definitions

Step	Language	Word	Meaning
1	Medieval Latin	litra	—
2	Ancient Greek	λίτρα	litra, a Sicilian silver coin; libra, a unit of...
3	Proto-Italic	*līðrā	—

litre — Etymology, Origin & Word History | Etymology Explorer