An assistant who is not part of the regular staff but helps as needed.

A person employed to assist in a role that usually has set staff members.

सहायक के रूप में कार्य करने वाला व्यक्ति

English Usage: The theater hired a supernumerary assistant for the production.

Hindi Usage: थिएटर ने प्रोडक्शन के लिए एक अस्थायी सहायक को नियुक्त किया।