A single species of immunoglobulin molecules produced by culturing a single clone of a hybridoma cell.
MAbs recognize only one chemical structure, i.e. they are directed against a single epitope of the antigenic substance used to raise the antibody.
Source:
PAC, 1992, 64, 143. 'Glossary for chemists of terms used in biotechnology (IUPAC Recommendations 1992)' on page 161 (https://doi.org/10.1351/pac199264010143)