acting

acting adjective uk/ˈæktɪŋ/ us   acting chairman/director, etc
someone who does a job for a short time while the person who usually does it is not there

исполняющий обязанности председателя/директора и т. д.

ACTING noun

[ U ] uk/ˈæktɪŋ/ us
the job of performing in plays and films

игра, работа актера
He's trying to get into acting .