subdeacon

noun4

1. •
   A layperson who acts as an assistant to the deacon during the celebration of mass.
2. •
   The highest of the minor orders below that of a deacon.
3. •
   (historical) A Catholic clerical rank in the major orders below that of a deacon.
4. •
   (historical) A Catholic cleric who assists the deacon at High Mass and normally reads the Epistle at the Eucharist.