What is the outward, physical manifestation of an organism called?

The term that describes the outward, physical manifestation of an organism is phenotype. The phenotype encompasses all observable traits and characteristics of an organism, which can include features such as appearance, behavior, and physiological traits. These traits result from the interaction of the organism's genotype, which is the genetic makeup, with environmental factors.

In contrast, genotype specifically refers to the genetic constitution of an organism, which may not always be evident in the physical traits expressed. Monohybrid and dihybrid crosses are concepts in genetics that refer to specific types of breeding experiments aimed at studying the inheritance of traits, but they do not pertain to the physical manifestations of those traits. Thus, phenotype is the correct answer as it directly relates to observable characteristics.