Stem cell

rudimentary cells in multi-cellular organisms, characterized by their continued ability to divide (self-renewal) and to differentiate (pluripotency or multipotency) into a range of specialised cell types

Description
Cells constituting the blastocyst in initial phases of development are embryonic stem cells, while adult stem cells are retained for continued maintenance of tissues later in life. Sometimes precursor cells that can still divide but are already committed to a certain lineage (multi- or unipotency) are also referred to as stem cells. For instance, hematopoietic stem cells are multipotent precursor cells that replenish blood cells by differentiation into erythrocytes, [leukocyte]]s and thrombocytes, but that have limited capacity to differentiate into other cell types.