polymorphism

American  

[pol-ee-mawr-fiz-uhm] / ˌpɒl iˈmɔr fɪz əm /

noun

1. the state or condition of being polymorphous.

2. Crystallography. crystallization into two or more chemically identical but crystallographically distinct forms.

3. Biology. the existence of an organism in several form or color varieties as a result of discontinuous variation.

4. Genetics. the presence of two or more distinct phenotypes in a population due to the expression of different alleles of a given gene, as human blood groups O, A, B, and AB.

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polymorphism British  

/ ˌpɒlɪˈmɔːfɪzəm /

noun

1. biology

   1. the occurrence of more than one form of individual in a single species within an interbreeding population

   2. the occurrence of more than one form in the individual polyps of a coelenterate colony

2. the existence or formation of different types of crystal of the same chemical compound

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polymorphism Scientific  

/ pŏl′ē-môr′fĭz′əm /

1. The occurrence of more than one form, as several alleles of a particular gene or winged and wingless forms of the same species. In bees, the presence of queen, worker, and drone is an example of polymorphism. Differences between the sexes and between breeds of domesticated animals are not considered examples of polymorphism.

2. The crystallization of a compound in at least two distinct forms. Diamond and graphite, for example, are polymorphs of the element carbon. They both consist entirely of carbon but have different crystal structures and different physical properties.

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Other Word Forms

• polymorphistic
  adjective

Etymology

Origin of polymorphism

First recorded in 1830–40; polymorph + -ism

Example Sentences

Polymorphism among the three genotypes did not prevent contig alignments but was sufficient to alter the locations of some of the fragile sites.

From Nature • Nov. 14, 2017

Polymorphism for Nt.BspQI sites can alter the distribution of these fragile regions, and contigs of different BNG maps may therefore overlap.

From Nature • Nov. 14, 2017

Polymorphism is lower in autosomal centromeric than non-centromeric regions, but not for the chromosome.

From Nature • Feb. 8, 2012

Polymorphism levels between synonymous and non-synonymous sites differ by an order of magnitude.

From Nature • Feb. 8, 2012

Polymorphism or dimorphism.—By this term I understand the co-existence in the same locality of two or more distinct forms, not connected by intermediate gradations, and all of which are occasionally produced from common parents.

From Contributions to the Theory of Natural Selection A Series of Essays by Wallace, Alfred Russel