Stem cells are undifferentiated cells in the human body that have the ability to develop into various specialized cells. These cells play a crucial role in the development and maintenance of tissues throughout the body. Synonyms for stem cells include progenitor cells, precursor cells, and germ cells. Progenitor cells are cells that have the potential to differentiate into a specific cell type. Precursor cells are immature cells that can differentiate into various types of cells. Germ cells are cells that give rise to sperm and egg cells. Other synonyms for stem cells include embryonic stem cells, adult stem cells, and induced pluripotent stem cells. These cells are potential therapeutic agents for various diseases and injuries.