Mendel's law

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. One of two principles of heredity first formulated by Gregor Mendel, founded on his experiments with pea plants and stating that the members of a pair of homologous chromosomes segregate during meiosis and are distributed to different gametes. Also called law of segregation.
2. n. The second of these two principles, stating that each member of a pair of homologous chromosomes segregates during meiosis independently of the members of other pairs, so that alleles carried on different chromosomes are distributed randomly to the gametes. Also called law of independent assortment.

GNU Webster's 1913

1. A principle governing the inheritance of many characters in animals and plants, discovered by Gregor J. Mendel (Austrian Augustinian abbot, 1822-84) in breeding experiments with peas. He showed that the height, color, and other characters depend on the presence of determinating factors behaving as units. In any given germ cell each of these is either present or absent.