Proliferative: Growing and increasing in number rapidly.
For example, the lymphoproliferative disorders are diseases in which there is malignant growth of lymphoid cells and of cells from the reticuloendothelial system (which take up and sequester inert particles).
As another example, the myeloproliferative disorders are malignancies of certain bone marrow cells including those that give rise to the red blood cells, the granulocytes (types of white blood cells), and the platelets (crucial to blood clotting).
"Proliferative" comes from the French who derived it from the Latin "proles" (offspring or descendants) + the combining form "-fer" (bearing). Cells that are proliferating are bearing offspring. p>