To make a public announcement; especially, to pronounce a public discourse upon a religious subject, or from a text of Scripture; deliver a sermon.To give earnest advice, especially on religious or moral subjects; also, to give advice obtrusively on religious or moral matters.To proclaim as a herald; declare; make known; publish.To inculcate (especially religious or moral truth or right conduct) in public or private discourse.To deliver, as a public religious discourse; pronounce, as a sermon.To affect by preaching, in a manner indicated by the context: as, to preach one into a penitent or a rebellious mood.To silence or suppress by preaching: as, to preach down unbelief.n. A sermon; a religious discourse.