What do we call a trait that can mask the expression of another trait?

A trait that can mask the expression of another trait is referred to as a dominant trait. In genetics, when two different alleles are present for a particular gene, the dominant allele will determine the phenotype, or observable traits, of an organism. This means that if an organism has one dominant allele and one recessive allele, the dominant allele's traits will be expressed while the recessive traits will not be visible.

For example, in pea plants, the allele for tall stems (dominant) can mask the expression of the allele for short stems (recessive). This trait interaction illustrates how dominant traits take precedence in determining an organism's characteristics. Understanding this concept is crucial for comprehending inheritance patterns and predicting traits in offspring.