Chaperone

[Monty]

any adult present in order to [maintain] order or [propriety] at an activity of young people, as at a [school dance].

[Cami]

A person who accompanies and looks after another person or group of people.

[Ernesto]

one of your friends you take with [you on] a groupdate when you dont feel [the need] to be [molested]

[Sommer]

(especially in the past) an older person, especially a woman, who stays with and takes care of a younger woman who is not married when she is in public: