What word describes the characteristics of an individual determined by both genes and the environment?

The term that describes the characteristics of an individual as determined by both genetic factors and environmental influences is "phenotype." This concept encompasses all observable physical and behavioral traits, which are the result of the interaction between an individual's genetic makeup and their environmental experiences.

In genetics, "genotype" refers specifically to the genetic constitution of an individual, which may not always manifest in observable traits due to environmental influences. "Hereditary traits" focuses primarily on the traits passed down from ancestors, but it does not capture the full scope of how those traits interact with environmental factors. The term "environment" alone refers to external factors and does not imply the combination of genetics and these factors that shape an individual's traits. Thus, "phenotype" is the most accurate term describing this dual influence.