to officially empower and authorize (someone) to act as a substitute in one's role or office
To act as a substitute for a person in their role or office
To officially empower, authorize, pronounce, and establish (someone) to be a deputy.
To enlist (someone) or make (someone) a member of
To enlist oneself (in something) or become a member (of something)
To enter (a name, etc.) in a register, roll or list