| a cell that upon division replaces its own numbers and also gives rise to cells that differentiate further into one or more specialized types, as various B cells and T cells. |

| stem cell n. An unspecialized cell that gives rise to a specific specialized cell, such as a blood cell. |
A cell from which a variety of other cells can develop through the process of cellular differentiation. Stem cells can produce only a certain group of cells (as with skin stem cells) or any cell in the body (as with embryonic stem cells).
Note: A major controversy involves the question of whether nonembryonic stem cells should be used for medical purposes.
stem cell n.
An unspecialized cell that gives rise to a specific specialized cell, such as a blood cell.