ho·mol·o·gous (hə-mŏlə-gəs, hō-)
1. Corresponding or similar in position, value, structure, or function.
2. Derived from the same species: a homologous graft.
3. Biology Similar in structure and evolutionary origin, though not necessarily in function, as the flippers of a seal and the hands of a human.
4. Immunology Relating to the correspondence between an antigen and the antibody produced in response to it.
a. Relating to chromosomes that have the same morphology and linear sequence of gene loci.
b. Relating to genes that are derived from a common ancestor.
6. Chemistry Belonging to or being a series of organic compounds, each successive member of which differs from the preceding member by a constant increment, especially by an added CH2 group.
[From Greek homologos, agreeing : homo-, homo- + logos, word, proportion; see leg- in the Appendix of Indo-European roots.]
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