BBCOR
BBCOR is a baseball bat performance standard created by the National Collegiate Athletic Association to certify the performance of composite baseball bats used in competition.
From the standard:
This standard went into effect on January 1, 2011 and all composite bats used in NCAA competition must meet the BBCOR standard in terms of their coefficient of restitution. The standard is used to certify "all baseball bats that are constructed with materials other than one-piece solid wood".