Where does “usage” come from?

Usage comes from Old French usage, meaning customary practice or habit.

usage (English): The manner or the amount of using; use; Habit or...

Definitions

Step	Language	Word	Meaning
1	Middle English	usage	—
2	Old French	usage	usage; use; habit; custom
3	Old French	-age	forms nouns with the sense of 'action or result...
4	Old Occitan	-atge	suffix used to form masculine nouns
5	Latin	-āticum	—