1. grouping of organisms: the science of classifying plants, animals, and microorganisms into increasingly broader categories based on shared features. Traditionally, organisms were grouped by physical resemblances, but in recent times other criteria such as genetic matching have also been used.
2. principles of classification: the practice or principles of classification
3. study of classification: the study of the rules and practice of classifying living organisms
[Early 19th century. < French taxonomie< Greek taxis (see taxis)]