genetics ge·net·ics (jə-nět'ĭks)
n.
The branch of biology that deals with heredity, especially the mechanisms of hereditary transmission and the variation of inherited traits among similar or related organisms.
The study of heredity, or how the characteristics of living things are transmitted from one generation to the next. Every living thing contains the genetic material that makes up DNA molecules. This material is passed on when organisms reproduce. The basic unit of heredity is the gene. (See chromosomes; dominant trait; genetic code; Gregor Mendel; recessive trait; and sexual reproduction.)