What does "reverend" mean?

Reverend: Worthy of reverence; entitled to respect mingled with fear and affection; venerable. A reverend sire among them came. Milton. They must give good example and reverend deportment in the face of their children. Jer. Taylor. Note: This word is commonly given as a title of respect to ecclesiastics. A clergyman is styled the reverend; a dean, the very reverend; a bishop, the right reverend; an archbishop, the most reverend.