phenotype

American  

[fee-nuh-tahyp] / ˈfi nəˌtaɪp /

noun

Genetics.

1. the observable constitution of an organism.

2. the appearance of an organism resulting from the interaction of the genotype and the environment.

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phenotype British  

/ ˌfiːnəʊˈtɪpɪk, ˈfiːnəʊˌtaɪp /

noun

1. the physical and biochemical characteristics of an organism as determined by the interaction of its genetic constitution and the environment Compare genotype

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phenotype Scientific  

/ fē′nə-tīp′ /

1. The physical appearance of an organism as distinguished from its genetic makeup. The phenotype of an organism depends on which genes are dominant and on the interaction between genes and environment.

2. Compare genotype

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phenotype Cultural  

1. The outward appearance of an organism; the expression of a genotype in the form of traits that can be seen and measured, such as hair or eye color.

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Other Word Forms

• phenotypic adjective
• phenotypical adjective
• phenotypically adverb

Etymology

Origin of phenotype

< German Phänotypus (1909); pheno-, -type

Compare meaning

How does phenotype compare to similar and commonly confused words? Explore the most common comparisons:

• genotype vs. phenotype

Explanation

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.

Example Sentences

The finding, the authors said, is consistent with the "domestication syndrome phenotype".

From BBC • Nov. 20, 2025

Introduced by our mutual friends, she was pitched to me as “tall and blond, with curly hair,” a historically winning phenotype for me, even if that “blond” mention was an elaborate brunette farce.

From Los Angeles Times • Nov. 1, 2024

By phenotype, Sackton means the actual expression of that trait, like having flippers or engaging in gaze following, as opposed to its genotype, meaning the genetic makeup that results in that trait.

From Salon • Sep. 13, 2024

"These can push cells to the brink of exhaustion and create an immunologic phenotype that is very, very often seen as a hallmark of progressive interstitial lung disease, or fibrosis of the lung."

From Science Daily • May 9, 2024

A phenotype, in contrast, refers to an organism’s physical or biological attributes and characteristics—the color of an eye, the shape of a wing, or resistance to hot or cold temperatures.

From "The Gene" by Siddhartha Mukherjee