classify

UK: /ˈklæsɪfaɪ/ US: /ˈklæsəˌfaɪ/ ,(klas′ə fī′)

Inflections of 'classify' (v): (⇒ conjugate)

classifies

v 3rd person singular

classifying

v pres p

classified

v past

classified

v past p

WordReference Random House Learner's Dictionary of American English © 2025

clas•si•fy /ˈklæsəˌfaɪ/   v. [~ + object] , -fied, -fy•ing. 

1. to arrange or organize by classes:
   She classified her students into three groups: low, average, and high.
2. to limit the availability of (information, etc.) to certain persons only:
   The government classified those documents until the year 2010.

clas•si•fi•a•ble, adj. 

WordReference Random House Unabridged Dictionary of American English © 2025

clas•si•fy  (klas′ə fī′), v.t., -fied, -fy•ing. 

1. to arrange or organize by classes;
   order according to class.
2. Government to assign a classification to (information, a document, etc.). Cf. classification (def. 5).
3. to limit the availability of (information, a document, etc.) to authorized persons.

• Latin classi(s) class + -fy
• 1790–1800

clas′si•fi′a•ble, adj. 
Synonyms

• 1. class, rank, rate, categorize, group.

Collins Concise English Dictionary © HarperCollins Publishers::

classify / ˈklæsɪˌfaɪ/ verb ( -fies, -fying, -fied)(transitive)

1. to arrange or order by classes; categorize
2. to declare (information, documents, etc) of possible aid to an enemy and therefore not available to people outside a restricted group

Etymology: 18th Century: back formation from classification

ˈclassiˌfiable adjective

ˈclassiˌfier noun