monoclonal

https://doi.org/10.1351/goldbook.09680
Arising from a single clone of cells.
Notes:
  1. In the case of immunoglobulin, "monoclonal" refers to its origin.
  2. Usually, the monoclonal antibody is of a single immunoglobulin class containing only one light chain type of either the K or L variety. It also refers to all antibody molecules having identical physical-chemical characteristics and antibody specificity. Monoclonal antibodies have very restricted structural diversity and they are homogeneous compared with polyclonal antibodies.
Source:
PAC, 2018, 90, 1121. 'Terminology of bioanalytical methods (IUPAC Recommendations 2018)' on page 1141 (https://doi.org/10.1515/pac-2016-1120)