designee
[ dez-ig-nee ]
/ ˌdɛz ɪgˈni /
noun
a person selected or designated to carry out a duty or role: If the judge is unavailable, his designee will hear the case.
a person named or selected for an office, position, etc., but not yet installed: She’s the CEO designee.
Origin of designee
First recorded in 1925–30;
design(ate) +
-ee