The outward expression of a genotype is referred to as its phenotype.

Here's a breakdown:

* Genotype: The genetic makeup of an organism, represented by the combination of alleles (alternative forms of a gene) it carries.

* Phenotype: The observable characteristics of an organism, including its physical traits, biochemical properties, and even behaviors.

For example, a person's genotype for eye color might be "Bb" (one dominant brown allele, "B", and one recessive blue allele, "b"). Their phenotype would be brown eyes because the brown allele is dominant.