The Collaborative International Dictionary of English v.0.48:

Circ \Circ\, n. [See Circus.]
   An amphitheatrical circle for sports; a circus. [R.] --T.
   Warton.
   [1913 Webster]

V.E.R.A. -- Virtual Entity of Relevant Acronyms (February 2016):

CIRC
       Cross Interleaved Reed-solomon Code (CD)