noun ap·o·mor·phy \ˈa-pə-ˌmȯr-fē\

Definition of apomorphy



biological taxonomy

  1. :  a specialized trait or character that is unique to a group or species :  a character state (such as the presence of feathers) not present in an ancestral form In this case, white flowers are a derived condition, an apomorphy, and red flowers are the ancestral condition. — James D. Mauseth, Botany: An Introduction to Plant Biology, 2009


\¦a-pə-¦mȯr-fik\ play less commonly


\ˈa-pə-ˌmȯrf\ play adjective As far as possible, it is assumed that each apomorphic evolutionary event only occurred once in the history of each group of related taxa … — C. Barry Cox and Peter D. Moore, Biogeography: An Ecological and Evolutionary Approach, 2010 … such apomorph characters are believed to be found only among the descendants of the ancestor in which the character first occurred. — Ernst Mayr, The Growth of Biological Thought, 1982

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Origin and Etymology of apomorphy

apomorphic or apomorphous (borrowed from German apomorph, from apo- “away from, apo-” + -morph “having such a structure, -morphous) + 2-y

First Known Use: 1969

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