The relationship of being homologous; a homologous relationship; specifically, such relationship in the context of the geometry of perspective.
An automorphism of the projective plane (representing a perspective projection) that leaves all the points of some straight line (the homology axis) fixed and maps all the lines through some single point (the homology centre) onto themselves.
A general way of associating a sequence of algebraic objects, such as abelian groups or modules, to a sequence of topological spaces; also used attributively: see Usage notes below.
Given a chain complex {Gn} and its associated set of homomorphisms {Hn}, the rule which explains how each Hn maps Gn into the kernel of Gn+1.
The relationship, between characteristics or behaviours, of having a shared evolutionary or developmental origin; specifically, a correspondence between structures in separate life forms having a common evolutionary origin, such as that between flippers and hands.
The presence of the same series of bases in different but related genes.
The relationship, between temporally separated human beliefs, practices or artefacts, of possessing shared characteristics attributed to genetic or historical links to a common ancestor.