classification

Grouping by type

Classification is the act or process of arranging things into groups or categories based on shared characteristics.

Scientists use classification to organize species into kingdoms, phyla, and so on; libraries classify books by subject.

A classification is also the category itself or the system of categories: What's the security classification on that document?

In machine learning, classification refers to algorithms that assign data points to predefined categories.

The verb is classify.

taxonomy

taxonomy

Science of categorical arrangement

speciesFinest taxonomic rank
genusTaxonomic rank above species
familyRelated people together

order · phylum · kingdom · domain · binomial · nomenclature · cladistics · phylogeny · systematics · morphology

categorization

category

A class of things

groupingArrangement by shared traits
sortingArranging into sequence
divisionSplitting into parts

subdivision · arrangement · organization · systematization · typology · schema · rubric · designation · labeling · coding

hierarchy

tier

Horizontal structural layer

rankPosition in hierarchy
levelHorizontal or uniform position
gradeClassification by rank

echelon · stratum · bracket · league · standing · position · status · rating · gradation · pecking order

security

clearance

Permitted passage or approval

confidentialMeant to stay secret
secretConcealed information
top secretHighest classification level

restricted · sensitive · redacted · compartmented · need-to-know · embargo · censorship · vetting · authorization

library

cataloguing

Recording items systematically

indexingSystematic organization for retrieval
archivingStoring for long-term keeping
call numberLibrary classification code

metadata · bibliography · cross-reference · filing · shelving · retrieval · database · repository · collection · accession

analysis

assessment

Formal evaluation of worth

evaluationDetermining worth or quality
examinationMethodical assessment or review
identificationEstablishing who someone is

determination · diagnosis · profiling · characterization · attribution · recognition · detection · screening · sorting · triage

Categories

biologycells, DNA, cell, biology, gene
classificationcategory, group, cataloging, grouping, kind
classificationshierarchical, categorical, taxonomic, ordinal, nominal
science termsbiology, chemistry, physics, math, experiment
juvenile biologybiology textbooks, biology experiments, cells, life cycles, science fair
library termsshelf, bookshelf, book selection, community library, spine

Opposites

order vs. disorder

classificationchaos

Complete disorder and confusion

disorder · disorganization · randomization · confusion · randomness

grouping vs. individuation

classificationindividuation

Distinguishing one from many

individualization · singularity · individuality · differentiation · distinction

secrecy status

classificationdeclassification

Lifting official secrecy designations

disclosure · release · publication · transparency · openness

Phrases

film classificationContent rating for cinema
security classificationOfficial secrecy designation
employee classificationHow staff are formally categorized
classification systemScheme for organizing categories
Dewey Decimal ClassificationLibrary cataloging by numbers
drug classificationCategorizing medicines by properties

Family

reclassification, classifications, declassification, misclassification

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