one of two alternative forms of a genes that can have the same place on homologous chromosomes and are responsible for alternative traits
one of two alternate forms of a gene that can have the same locus on homologous chromosomes and are responsible for alternative traits; "some alleles are dominant over others"
(genetics) either of a pair (or series) of alternative forms of a gene that can occupy the same locus on a particular chromosome and that control the same character