1) Aide 2) Auxiliary 1) An assistant 2) An assistant to a bishop 3) Assistant 4) Help 5) Helper 6) Supporter 
bishop assisting a diocesan bishop and having the right of succession
• (n.) One who aids another; an assistant; a coworker. • (n.) The assistant of a bishop or of a priest holding a benefice.
Co`ad·ju'tor noun [ Latin See Co -, and Aid .] 1. One who aids another; an assistant; a coworker. « Craftily outwitting her perjured coadjutor . Sheridan. » 2. (R. C. Ch.) The assistant of a bishop or of a priest holding a benefice. 
[n] - an assistant to a Bishop
coadjutor 1. A helper. 2. A bishop who assists a diocesan bishop.
noun an assistant to a bishop
an assistant. · an assistant to a bishop or other ecclesiastic. · a bishop who assists another bishop, with the right of succession.