Noun

• S: (n) group, grouping (any number of entities (members) considered as a unit)
• S: (n) grouping (the activity of putting things together in groups)
• S: (n) grouping, pigeonholing (a system for classifying things into groups)
• direct hypernym / inherited hypernym / sister term
• S: (n) classification system (a system for classifying things)
• S: (n) Dewey decimal classification, Dewey decimal system, decimal system of classification (a system used by libraries to classify nonfictional publications into subject categories; the subject is indicated by a three-digit numeral and further specification is given by numerals following a decimal point; publications are shelved by number)
• S: (n) hierarchical classification system (a classification system where entries are arranged based on some hierarchical structure)
• S: (n) file system, filing system (a system of classifying into files (usually arranged alphabetically))
• S: (n) grouping, pigeonholing (a system for classifying things into groups)
• S: (n) rating system, scoring system (a system of classifying according to quality or merit or amount)
• S: (n) ABO blood group system, ABO system, ABO group (a classification system for the antigens of human blood; used in blood transfusion therapy; four groups are A and B and AB and O)
• derivationally related form

Verb

• S: (v) group (arrange into a group or groups) "Can you group these shapes together?"
• S: (v) group, aggroup (form a group or group together)