Where does “granter” come from?

granter (Anglo-Norman) comes from Old French granter, from Old French greanter — to promise, assure, guarantee, confirm, ratify.

Ancestry of “granter”, step by step

Step	Language	Word	Meaning
1	Old French	granter	—
2	Old French	greanter	to promise, assure, guarantee, confirm, ratify

granter — Etymology, Origin & Word History | Etymology Explorer