The Collaborative International Dictionary of English v.0.48:

Surcingle \Sur"cin`gle\, n. [OE. sursengle, OF. sursangle. See
   Sur-, and Cingle, Shingles.]
   1. A belt, band, or girth which passes over a saddle, or over
      anything laid on a horse's back, to bind it fast.
      [1913 Webster]

   2. (Eccl.) The girdle of a cassock, by which it is fastened
      round the waist.
      [1913 Webster]