Chalone is a term used in biology to refer to a group of proteins that regulate cell growth and differentiation. Synonyms for this word are numerous, and they reflect the diverse functions of the protein group. Some of the synonyms frequently used in scientific literature include paracrine factor, growth inhibitor, and differentiation-inducing factor. Other alternatives for the term chalone are differentiation factors, antimitogenic factors, and tumor suppressor factors. The diversity of synonyms for chalone reflects the complexity of the biochemical pathways involved in regulating cell growth and development. Understanding these pathways and the functions of chalones is an important step in developing new treatments for diseases such as cancer.