CMAC is a block cipher-based message authentication code algorithm. It may be used to provide assurance of the authenticity and the integrity of binary data. This mode of operation fixes security deficiencies of CBC-MAC).
CMAC is the name defined by NIST. It is also known as OMAC1, which in turn sometimes is abbreviated to OMAC (which includes OMAC1 and OMAC2 according to one of the authors of the OMAC paper).