Whereas the "genotype" is the genetic makeup of an organism, the phenotype is how genetic and environmental influences come together to create an organism’s physical appearance and behavior.

The noun phenotype entered the lexicon around 1910, adapted from the German word phänotypus, based on the Greek phaino, which means "shining," or “appearance.” The phenotype can include not only the physical appearance of the organism, but also its behavior — for example, the migration of geese — and the products of that behavior. This includes "instinct," such as that of a cowbird causing it to lay its eggs in another bird’s nest. Variation in phenotype is an important element in evolution.

Definitions of phenotype
  1. noun
    what an organism looks like as a consequence of the interaction of its genotype and the environment
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    type of:
    composition, constitution, make-up, makeup, physical composition
    the way in which someone or something is composed
Word Family

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