Preaching is only one function of the ordained ministry in the Episcopal Church and so preacher is not an appropriate synonym for bishop, priest or deacon
A preacher is a person, usually a member of the clergy, who preaches sermons as part of a church service. someone who talks about a religious subject in a public place, especially at a church
(The) Solomon, the author of Ecclesiastes (the Preacher) The glorious preacher Saint John Chrysostom (347-407 ) The king of preachers Louis Bourdaloue (1632-1704 ) The little preacher Samuel de Marets, Protestant controversialist (1599-1663 )