Churchman is a related term of deacon.
As nouns the difference between churchman and deacon
is that
churchman is a person (originally a man) of authority in a religious organization; a cleric while
deacon is (church history) a designated minister of charity in the early church (see acts 6:1-6).
As a verb deacon is
(christianity|music) for a choir leader to lead a hymn by speaking one or two lines at a time, which are then sung by the choir.