n. the condition in which the chromosome number of a cell is not an exact multiple of the normal basic (haploid) number. See monosomy; trisomy. Compare euploidy. —aneuploid adj., n.... aneuploidy
n. a condition in which pairs of homologous chromosomes fail to separate during meiosis or a chromosome fails to divide at *anaphase of mitosis or meiosis. It results in a cell with an abnormal number of chromosomes (see monosomy; trisomy).... nondisjunction
Health Encyclopedia