sub-deacon

/S AH1 B D IY0 K AH0 N/
noun
  1. 1

    (chiefly historical) A Catholic clerical rank in the major orders below that of a deacon.

  2. 2

    (chiefly historical) A Catholic cleric who assists the deacon at High Mass and normally reads the Epistle at the Eucharist.

  3. 3

    The highest of the minor orders below that of a deacon

Source: https://en.wiktionary.org/wiki/sub-deacon, https://en.wiktionary.org/wiki/subdeacon