Preacher \Preach"er\, n. [Cf. OF. preeschierre, prescheur, F. pr[^e]cheur, L. praedicator.] 1. One who preaches; one who discourses publicly on religious subjects. How shall they hear without a preacher? --Rom. x. 14. 2. One who inculcates anything with earnestness. No preacher is listened to but Time. --Swift. {Preacher bird} (Zo["o]l.), a toucan.