classify

American  

[klas-uh-fahy] / ˈklæs əˌfaɪ /

verb (used with object)

• classifies,
  present (3rd person singular)
• classified,
  past participle,  past
• classifying
  present participle

1. to arrange or organize by classes; order according to class.

   Synonyms:

   group, categorize, rate, rank, class

2. to assign a classification to (information, a document, etc.).

3. to limit the availability of (information, a document, etc.) to authorized persons.

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classify British  

/ ˈklæsɪˌfaɪ /

verb

1. to arrange or order by classes; categorize

2. government to declare (information, documents, etc) of possible aid to an enemy and therefore not available to people outside a restricted group

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Other Word Forms

Derived Forms

• classifier
  noun
• unclassifiableness
  noun
• misclassify
  verb (used with object)
• overclassify
  verb (used with object)
• preclassify
  verb (used with object)
• classifiable
  adjective
• nonclassifiable
  adjective
• unclassifiable
  adjective
• unclassifying
  adjective
• unclassifiably
  adverb

Inflected Forms

Participles

• classifying
  present
• classified
  past

Conjugated Forms

Present

• classify
  simple
• classifies
  simple
• have classified
  perfect
• has classified
  perfect
• am classifying
  progressive
• are classifying
  progressive
• is classifying
  progressive
• have been classifying
  perfect progressive
• has been classifying
  perfect progressive

Past

• classified
  simple
• had classified
  perfect
• was classifying
  progressive
• were classifying
  progressive
• had been classifying
  perfect progressive

Future

• will classify
  simple
• will have classified
  perfect
• will be classifying
  progressive
• will have been classifying
  perfect progressive

Etymology

Origin of classify

First recorded in 1790–1800; from Latin classi(s) class + -fy

Explanation

Humans seem to have the need to classify things, arranging them into different classes by such unifying traits as size, color, or shape. It’s fine to do this to inanimate objects, but doing it to people can be very wrong. The word classify contains the base word class, which means "category" and comes from the Latin classis, which actually referred to an army or group called to arms. It eventually came to mean "a group," and thus classify means "to group." As a security measure, you can also classify information that is not to be shared. Writer Ambrose Bierce once said, “The small part of ignorance that we arrange and classify we give the name of knowledge.”

Example Sentences

See Examples For:

classify classifies classified classifying

It was a big enough job for the two scholars to classify all the known musical instruments of the world.

From The Wall Street Journal ● Aug. 7, 2026

For much of Wales and Northern England, the three-day run of temperatures of 25C or above required to classify as a heatwave will not be met.

From BBC ● Jul. 28, 2026

Critics say Japan also differs from many other countries by having out-of-date building regulations that can classify data centres as offices and not industrial facilities.

From Barron's ● Jul. 17, 2026

But experts cautioned against reading too much into year-over-year numbers that can fluctuate based on many factors — including how authorities classify and count certain offenses.

From Los Angeles Times ● Jul. 3, 2026

“I believe some might classify you as weak? Now, have you seen the fellow from the movie house?”

From "Salt to the Sea" by Ruta Sepetys

OpenAI classifies model risk into two tiers, with “critical” representing the highest level of capability threat, above “high.”

From The Wall Street Journal ● Aug. 7, 2026

That’s far from the 20% drop that classifies a bear market, Mayfield pointed out.

From MarketWatch ● Jul. 12, 2026

The UN agency classifies El Nino events as weak, moderate, strong or very strong, meaning it is set to reach the third-highest level out of four.

From Barron's ● Jul. 3, 2026

The European Chemicals Agency classifies the chemical as harmful to aquatic life.

From Science Daily ● Jun. 9, 2026

In Plato’s allegory of the metals, the philosopher classifies men into groups of gold, silver, and lead.

From "Long Walk to Freedom" by Nelson Mandela

Researchers classified a severe medical outcome as one involving life-threatening effects, significant lasting disability, or death.

From Science Daily ● Aug. 18, 2026

Since mid‑July, Rijkswaterstaat, the national water management agency, has classified the situation as an "actual water shortage".

From Barron's ● Aug. 15, 2026

This is one benefit of doing classified work.

From The Wall Street Journal ● Aug. 13, 2026

According to the campaign’s screenshot, the chatbot replied that its “origins are classified under about seventeen different committee review processes.”

From Los Angeles Times ● Aug. 11, 2026

But trusting him with the classified details of my heart turned out to be a rookie mistake.

From "Americanized" by Sara Saedi

The researchers note that a separate recent study by Zanno and Napoli reached a similar conclusion using different methods, classifying Jane and Petey as two distinct species of Nanotyrannus.

From Science Daily ● Jun. 22, 2026

The region, made up of mountains surrounded by a desert steppe, receives just over 100 millimeters of annual rainfall, classifying it as an desert.

From Barron's ● Jun. 15, 2026

In Kentucky, lawmakers recently passed a bill classifying TV-viewing patterns as “sensitive data” deserving of broader legal protections and transparency measures.

From Slate ● May 3, 2026

"We are also continuing to work with providers who are in the process of correctly classifying courses," a spokesperson added.

From BBC ● Apr. 20, 2026

Before that, she’d been working as a file clerk at a nearby hospital, classifying the records of patients who had died.

From "Dreaming in Cuban" by Cristina García

Related Words

• allocate
• analyze
• arrange
• distribute
• divide
• label
• organize
• segregate