respect to a particular trait or condition, an individual who has inherited
two different alleles, usually one normal and the other abnormal, at a particular
Definition from: GeneReviews
from the University of Washington and the National Center for Biotechnology Information
Heterozygous refers to having inherited different forms of a particular gene from each parent. A heterozygous genotype stands in contrast to a homozygous genotype, where an individual inherits identical forms of a particular gene from each parent.