The Collaborative International Dictionary of English v.0.48:

Reverend \Rev"er*end\, a. [F. r['e]v['e]rend, L. reverendus, fr.
   revereri. See Revere.]
   Worthy of reverence; entitled to respect mingled with fear
   and affection; venerable.
   [1913 Webster]

         A reverend sire among them came.         --Milton.
   [1913 Webster]

         They must give good example and reverend deportment in
         the face of their children.              --Jer. Taylor.
   [1913 Webster]

   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.
         [1913 Webster]

WordNet (r) 3.0 (2006):

reverend
    adj 1: worthy of adoration or reverence [syn: reverend,
           sublime]
    n 1: a member of the clergy and a spiritual leader of the
         Christian Church [syn: clergyman, reverend, man of the
         cloth] [ant: layman, layperson, secular]
    2: a title of respect for a clergyman