Is it ensure, insure, or assure?
early 15c., "branch out," from Middle French ramifier (early 14c.), from Medieval Latin ramificare "to form branches," from Latin ramus "branch" (see ramus) + root of facere "to make" (see factitious). Related: Ramified; ramifying.
ramify ram·i·fy (rām'ə-fī')v. ram·i·fied, ram·i·fy·ing, ram·i·fies To branch.