what is nondisjunction?
MEIOSIS (meioses) â¢ NONDISJUNCTION (noun). The noun NONDISJUNCTION has 1 sense: 1. meiosis in which there is a failure of paired homologous chromosomes to separate; results in an abnormal number of chromosomes in the daughter cells. Familiarity information: NONDISJUNCTION used as a noun is very rare. Dictionary entry details. â¢ NONDISJUNCTION (noun).