In genetics, the greater influence by one of a pair of genes (alleles) that affect the same inherited trait. If an individual pea plant that has one allele for tallness and one for shortness is the same height as an individual that has two alleles for tallness, the tallness allele is said to be completely dominant. If such an individual is shorter than an individual that has two tallness alleles but still taller than one that has two shortness alleles, the tallness allele is said to be partially or incompletely dominant and the shortness allele is said to be recessive (see recessiveness).

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