Definition of "homologous"

Showing a degree of correspondence or similarity.

1. (mathematics) In corresponding proportion.  quotations  examples

   Quotations

   • Of equiangle triangles, the ſides that are about equall angles are proportionall, and the ſides that ſubtend the equall angles are homologous.

     1655, Thomas Stanley, “[Thales.] Chapter VII.. Of His Geometry.”, in The History of Philosophy. […], volume I, London: […] Humphrey Moseley, and Thomas Dring, […], 1st part ([Containing Those on whom the Attribute of Wise was Conferr’d]), page 18

2. (biology) Corresponding to a similar structure in another life form with a common evolutionary origin.  quotations

   Quotations

   • Lobules, homologous in structure, recur again only in the Gondwanalandic families Lepidolaenaceae and Jubulopsidaceae thus in the Lepidolaenineae.

     1992, Rudolf M[athias] Schuster, The Hepaticae and Anthocerotae of North America: East of the Hundredth Meridian, volume V, New York, N.Y.: Columbia University Press, page 4

3. (chemistry) Belonging to a series of aliphatic organic compounds that differ only by the addition of a CH₂ group.  examples

4. (genetics) Having the same morphology as another chromosome or locus; relating to a homologue.  examples

5. (cultural anthropology, structural anthropology) Playing the same role as seen in another culture, whether by historical connection, psychological archetype, convergent cultural evolution, or otherwise (as may be hypothesized but not known with certainty by current science), as for example with the cryptozoologic concepts of yeti and sasquatch, the use of polite and familiar pronouns, or other similarities.