Open English Wordnet
Nouns
(n)categorization, categorisation, classification, compartmentalization, compartmentalisation, assortmentthe act of distributing things into classes or categories of the same type
(n)classification, categorization, categorisationa group of people or things arranged by class or category
(n)classification, categorization, categorisation, sortingthe basic cognitive process of arranging into classes or categories
(n)classificationrestriction imposed by the government on documents or weapons that are available only to certain authorized people