The Collaborative International Dictionary of English v.0.48:

Suffragan \Suf"fra*gan\, a. [F. suffragant, L. suffragans, p.
   pr. of suffragari to support with one's vote, to be
   favorable. See Suffrage.]
   Assisting; assistant; as, a suffragan bishop.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Suffragan \Suf"fra*gan\, n. [F. suffragant: cf. LL.
   suffraganeus. See Suffragan, a.]
   1. An assistant.
      [1913 Webster]

   2. (Eccl.) A bishop considered as an assistant, or as
      subject, to his metropolitan; an assistant bishop.
      [1913 Webster]

WordNet (r) 3.0 (2006):

suffragan
    n 1: an assistant or subordinate bishop of a diocese [syn:
         suffragan, suffragan bishop]