adj.
a title or form of address to members of the clergy.
n.
informal a clergyman.
Usage
The traditionally correct way to use Reverend when addressing members of the clergy is the Reverend James Smith or the Reverend J. Smith, rather than Reverend Smith or simply Reverend.
Etymology
ME: from OFr., or from L. reverendus ‘person to be revered’, gerundive of revereri (see revere).