The capitalization of "Corybant" makes it sound as though it refers to an individual. I think it refers to a group of priests. I would not care to join them, since I have read that in their frenzy, they castrated themselves. Here is a link to a discussion of Cybele, which regrettably doesn't mention the priests:
http://www.bcholmes.org/wicca/myths/cybele.html

Corybant is indeed singular. The plural is Corybantes. For a bit mmore information on the Corybantes see:
http://www.perseus.tufts.edu/cgi-bin/ptext?doc=Perseus:text:1999.04.0062&query=head=#2965

Bingley