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1. Chemistry See polymorphism.
2. Biology The occurrence of two or more distinct forms, as of an organism during its life cycle or of cells of a certain type.

ple′o·mor′phic adj.


(ˌpliːəˈmɔːˌfɪzəm) or


1. (Biology) the occurrence of more than one different form in the life cycle of a plant or animal
2. (Chemistry) the occurrence of more than one different form of crystal of one chemical compound; polymorphism
ˌpleoˈmorphic adj


(ˌpli əˈmɔr fɪz əm)

1. the occurrence of two or more forms in the life cycle of an organism.
2. the ability of a microorganism to change shape under varying conditions.
ple`o•mor′phic, adj.

pleomorphism, pleomorphy

the existence of a plant or animal in two or more distinct forms during a life cycle. Also called polymorphism.pleomorphic, pleomorphous, adj.
See also: Biology
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.pleomorphism - (chemistry) the existence of different kinds of crystal of the same chemical compound
chemical science, chemistry - the science of matter; the branch of the natural sciences dealing with the composition of substances and their properties and reactions
chemical phenomenon - any natural phenomenon involving chemistry (as changes to atoms or molecules)
dimorphism - (chemistry) the property of certain substances that enables them to exist in two distinct crystalline forms
2.pleomorphism - (biology) the appearance of two or more distinctly different forms in the life cycle of some organisms
biological science, biology - the science that studies living organisms
organic phenomenon - (biology) a natural phenomenon involving living plants and animals


n. pleomorfismo, cualidad de asumir o tener formas diferentes.
References in periodicals archive ?
Hence, a decrease in density leads to an increase in pleomorphism and polymegathism.
Necrosis, nuclear pleomorphism, and mitotic activity were not detected.
The myxoid foci are hypocellular, but they still show pleomorphism.
The characteristic cytomorphologic features noted correspond to the histologic features and include large polygonal to round cells with granular to flocculent cytoplasm, well defined cell borders, mild nuclear pleomorphism, vesicular nuclei, perinuclear clearing, and small to indistinct nucleoli.
On microscopy, sections showed interlacing fascicles of spindled cells with diffuse pleomorphism (Figure 2a), increased mitotic activity (up to 16 mitoses per 10 HPF with atypical forms) (Figure 2b), and a focally infiltrative border.
The histologic architecture and pattern of tissue invasion closely resemble ILC; however, the cellular pleomorphism and nuclear atypia are more consistent with IDC.
They also found, contrary to the conventional understanding, a large degree of pleomorphism in normal cell nuclei, as well as "not-so-prominent" differences between normal and malignant cells in the nucleus-to-cytoplasm ratio.
However, the bacterium can exhibit variability and pleomorphism on Gram staining: forms range from bacilli in nutrient-depleted media to cocci arranged in short chains in nutrient-rich media (1,2).
At the heart of all of Rau's therapies, and indeed all of Sanum pleomorphism theory, first elucidated by Prof.
Pleomorphism may include fibroadenoma and malignant adenomyoepithelial elements.
3,4,6,7) Pleomorphism or atypia are not expected features, however, focal calcification, stromal hyalinization, and necrosis are sometimes present.
Cellular pleomorphism, mitotic figures, and necrosis are absent.