Meronomy

A meronomy or partonomy is a type of hierarchy that deals with part–whole relationships, in contrast to a taxonomy whose categorisation is based on discrete sets. Accordingly, the unit of meronomical classification is meron, while the unit of taxonomical classification is taxon. These conceptual structures are used in linguistics and computer science, with applications in biology. The part–whole relationship is sometimes referred to as "HAS-A", and corresponds to object composition in object-oriented programming. The study of meronomy is known as "mereology", and in linguistics a "meronym" is the name given to a constituent part of, a substance of, or a member of something. "X" is a meronym of "Y" if an X is a part of a Y.
In knowledge representation.
In formal terms, in the context of knowledge representation and ontologies, a meronomy is a partial ordering of concept types by the part–whole relation.
The classic study of parts and wholes, mereology, has three axioms: the part-of relation is
Meronomies may be represented in Semantic Web languages such as OWL and SKOS. In natural languages they are represented by meronyms and holonyms.