A / arrŏgātor
noun

arrŏgātor

gen. arrŏgātōris · gender masculine · decl. 3rd
he that adopts
he that adopts one in the place of a child (cf. arrogatio), Dig. 1, 7, 2; 1, 7, 19; 1, 7, 22; 1, 7, 40.