taxonomy

n. study of the principles of scientific classification (Biology)

Taxonomy is the practice and science of classification. The word comes from the Greek , taxis, 'order' + , nomos, 'law' or 'science'. Taxonomies, or taxonomic schemes, are composed of taxonomic units known as taxa (singular taxon), or kinds of things that are arranged frequently in a hierarchical structure, typically related by subtype-supertype relationships, also called parent-child relationships. In such a subtype-supertype relationship the subtype kind of thing has by definition the same constraints as the supertype kind of thing plus one or more additional constraints. For example, car is a subtype of vehicle. So any car is also a vehicle, but not every vehicle is a car. So, a thing needs to satisfy more constraints to be a car than to be a vehicle.
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Noun
1. a classification of organisms into groups based on similarities of structure or origin etc
(hypernym) hierarchy
2. (biology) study of the general principles of scientific classification
(hypernym) systematics
(hyponym) cladistics, cladisitic analysis
(classification) biology, biological science
3. practice of classifying plants and animals according to their presumed natural relationships
(hypernym) categorization, categorisation, classification, compartmentalization, compartmentalisation, assortment

(n.)
That division of the natural sciences which treats of the classification of animals and plants; the laws or principles of classification.
  

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