From Wesleyan Discipline
678. A minister who serves as the sole pastor of a church shall be referred to simply as “the pastor.” The term “senior pastor” shall be applied to the presiding minister of a multiple pastoral staff. The pastor shall be expected to carry out the full pastoral function as set forth in 675, and ultimate responsibility for the same shall rest upon the presiding pastor. An assistant pastor is a helping member of a multiple staff who normally is assigned more limited and specific aspects of the pastoral function (741).