cell population proliferation This term was moved out from being a child of 'cellular process' because it is a cell population-level process, and cellular processes are restricted to those processes that involve individual cells. Also note that this term is intended to be used for the proliferation of cells within a multicellular organism, not for the expansion of a population of single-celled organisms. GO:0008283 The multiplication or reproduction of cells, resulting in the expansion of a cell population. cell proliferation cellular process