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homology

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noun ho·mol·o·gy \hō-ˈmä-lə-jē, hə-\

Definition of homology

plural

homologies

  1. 1 :  a similarity often attributable to common origin

  2. 2 a :  likeness in structure between parts of different organisms (as the wing of a bat and the human arm) due to evolutionary differentiation from a corresponding part in a common ancestor — compare analogy b :  correspondence in structure between a series of parts (as vertebrae) in the same individual

  3. 3 :  similarity of nucleotide or amino acid sequence (as in nucleic acids or proteins)

  4. 4 :  a branch of the theory of topology concerned with partitioning space into geometric components (as points, lines, and triangles) and with the study of the number and interrelationships of these components especially by the use of group theory —called also homology theory — compare cohomology




Medical Dictionary

homology

play
noun ho·mol·o·gy \hō-ˈmäl-ə-jē, hə-\

Medical Definition of homology

plural

homologies

  1. 1a:  likeness in structure between parts of different organisms due to evolutionary differentiation from the same or a corresponding part of a remote ancestor—compare analogy, homomorphyb:  correspondence in structure between different parts of the same individual

  2. 2a:  the relation existing between chemical compounds in a series whose successive members have in composition a regular difference especially of one carbon and two hydrogen atoms CH2b:  the relation existing among elements in the same group of the periodic tablec:  similarity of nucleotide or amino acid sequence (as in nucleic acids or proteins)




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