A lymphocyte of B lineage that is devoted to secreting large amounts of immunoglobulin. [ GOC:add http://openisbn.com/search.php?q=0721601464&isbn=1/ GOC:tfm http://purl.obolibrary.org/obo/go/references/0000031 http://openisbn.com/search.php?q=0781735149&isbn=1/ ]