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

All of them must have pedals to classify as an e-bike.

From Los Angeles Times ● Jul. 21, 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

Some biologists classify viruses as “life forms.” because they are not strictly known to be alive.

From "The Hot Zone" by Richard Preston

Sunscreen is regulated as a cosmetic in Europe, leading to more variety than in the U.S., which classifies it as an over-the-counter drug.

From The Wall Street Journal ● Aug. 14, 2026

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

From MarketWatch ● Jul. 12, 2026

The biotech, which classifies itself as a neuroscience company, is developing nonaddictive treatments for chronic pain.

From Barron's ● Jun. 16, 2026

Foro Penal said that, as of 20 April, 473 people it classifies as political prisoners had been released, while more than 500 are thought to remain incarcerated.

From BBC ● Apr. 25, 2026

He learns the endless terms, the vocabulary that classifies the details of ancient buildings, writing them on separate index cards and making illustrations on the back: architrave, entablature, tympanum, voussoir.

From "The Namesake" by Jhumpa Lahiri

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

Some of these will be strong enough to be classified as typhoons – as was the case with Dolphin.

From BBC ● Aug. 8, 2026

The meteorite was classified as a CM1/2 carbonaceous chondrite, placing it between the petrographic CM1 and CM2 categories.

From Science Daily ● Aug. 8, 2026

Some documents that had been made public were classified all over again.

From "The Woman All Spies Fear" by Amy Butler Greenfield

Later in the fall, OpenAI changed the designation of GPT-5, classifying it as less dangerous.

From The Wall Street Journal ● Jul. 26, 2026

"What we think is important to highlight is that without waveform models like ours, we could be detecting black hole mergers in dark matter environments, but systematically classifying them as having occurred in vacuum."

From Science Daily ● May 19, 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

Aureliano had finished classifying the alphabet of the parchments, so that when Melquíades asked him if he had discovered the language in which they had been written he did not hesitate to answer.

From "One Hundred Years of Solitude" by Gabriel Garcia Marquez

Related Words

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