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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.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(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
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(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.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.

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
-Ologies & -Isms. Copyright 2008 The Gale Group, Inc. All rights reserved.
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
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.


n. pleomorfismo, cualidad de asumir o tener formas diferentes.
English-Spanish Medical Dictionary © Farlex 2012
References in periodicals archive ?
Histologically, malignant PTTs show severe nuclear atypia, marked cellular pleomorphism with atypical mitoses, dyskeratotic cells and infiltrating margins.
Meningiomas are classified according to the neoplasm characteristics, such as tissue invasion, mitotic index, cellular pleomorphism, necrosis and extra neural metastasis, which are malignancy indicators, in addition to the classification in subtypes: meningothelial, fibromatous, transitional, psammomatous, among others (HIGGINS et al., 2017; LOUIS et al., 2016).
The basaloid shape cells exhibited features of nuclear atypia such as nuclear and cellular pleomorphism and nuclear hyperchromatism.
Nuclear pleomorphism, marked cytologic atypia including squamous and clear cell differentiation, and increased mitotic figures more than 4 mitoses per 10 HPFs were described (Figure 4).
If there are cellular pleomorphism, mitotic activity, necrosis and atypical change; we should consider malignant transformation.8
These tumors are characterized by cytological pleomorphism, increased mitotic and proliferation indices, and have a worse prognosis.
In addition, the four participating pathologists in China were asked to assess surface maturation, nuclear enlargement, nuclear hyperchromasia, nuclear stratification, nuclear pleomorphism, loss of nuclear polarity, architectural complex, and abnormal mitoses, features which have been reported in the diagnosis of dysplasia (Table 1) [6].
Sebaceous carcinoma has been defined by the WHO as "a malignant tumor composed of sebaceous cells of varying maturity that are arranged in sheets and/or nests with different degrees of pleomorphism, nuclear atypia, and invasiveness" [1].
No atypia, pleomorphism, necrosis, or mitotic activity was seen.
Also, central corneal endothelium morphology assessment was conducted, which includes central corneal thickness (CCT), endothelial cell density (ECD), corneal endothelial cell size variations as the percentage of the abnormal sizes (corneal polymegathism), and corneal cell shape variations as the percentage of the hexagonal cells (corneal pleomorphism).
Left: There is little pleomorphism, although nuclear contour irregularities, grooves, and folds are seen.
(19,20,21,22,23,24,25,26,27) Specular microscopic examinations showed an increased variation in endothelial cell size (polymegathism) and shape (pleomorphism) in eyes with keratoconus.