Homology
Full definition of homology
Noun
homology
(plural homologies)- A homologous relationship.
- (biology) A correspondence of structures in two life forms with a common evolutionary origin, such as flippers and hands.
- (chemistry) The relationship between the elements in the same group of the periodic table, or between organic compounds in a homologous series.
- (mathematics) A theory associating a system of quotient groups to each topological space.
- (mathematics) A system of quotient groups associated to a topological space.
- (genetics) The presence of the same series of bases in related genes.
Usage notes
(biology) For a discussion of the use of the term homology (and by association homologous) in biology, see: Patterson, Colin. "Homology in Classical and Molecular Biology." Molecular Biology and Evolution 5, no. 6 (November 1988): 603–625. http://mbe.oxfordjournals.org/cgi/reprint/5/6/603.pdf (accessed 18 December 2009; archived 18 December 2009, http://www.webcitation.org/5m7rn4rCe )
(mathematics) When used attributively before the name of a topological space, as in "homology n-sphere" or "homology manifold", the reference is to a space whose homology is the same as that of the space mentioned: an homology manifold, for example, is a space whose homology is that of some manifold.