An apostle is someone who is sent out on a specific mission as an envoy or representative of the sender. The term "apostle" comes from the Greek word "apostolos," which means "one who is sent off". In the Christian faith, apostles were those entrusted by Jesus to help organize the church and spread the message of His teachings. The New Testament has two primary usages of the word apostle. The first is in specifically referring to the twelve apostles of Jesus Christ. The second usage is more general and refers to anyone who was "sent" and could be called an apostle.
The role of an apostle outside that of the twelve apostles of Jesus Christ is not entirely clear. From the definition of the word, the closest thing today to an apostle, in the general sense, is a missionary. A modern-day Apostle in the tradition of the Apostolic-Prophetic movement is one who is "called and sent by Christ to have the spiritual authority, character, gifts and abilities to successfully reach and establish people in Kingdom truth and order, especially through founding and overseeing local churches” . However, to prevent confusion, it is likely best to not use the term apostle to refer to any position in the church today.
