complex 1 of 3

Definition of complexnext

complex

2 of 3

noun

1
as in facility
a structure that is designed and built for a particular purpose an apartment complex

Synonyms & Similar Words

2
as in system
something made up of many interdependent or related parts a complex of government programs designed to assist the needy

Synonyms & Similar Words

complex

3 of 3

verb

Synonym Chooser

How does the adjective complex differ from other similar words?

Some common synonyms of complex are complicated, intricate, involved, and knotty. While all these words mean "having confusingly interrelated parts," complex suggests the unavoidable result of a necessary combining and does not imply a fault or failure.

a complex recipe

When is complicated a more appropriate choice than complex?

While the synonyms complicated and complex are close in meaning, complicated applies to what offers great difficulty in understanding, solving, or explaining.

complicated legal procedures

When might intricate be a better fit than complex?

The synonyms intricate and complex are sometimes interchangeable, but intricate suggests such interlacing of parts as to make it nearly impossible to follow or grasp them separately.

an intricate web of deceit

When is it sensible to use involved instead of complex?

Although the words involved and complex have much in common, involved implies extreme complication and often disorder.

a rambling, involved explanation

When would knotty be a good substitute for complex?

While in some cases nearly identical to complex, knotty suggests complication and entanglement that make solution or understanding improbable.

knotty ethical questions

How does the adjective complex differ from other similar words?

Some common synonyms of complex are complicated, intricate, involved, and knotty. While all these words mean "having confusingly interrelated parts," complex suggests the unavoidable result of a necessary combining and does not imply a fault or failure.

a complex recipe

When is complicated a more appropriate choice than complex?

While the synonyms complicated and complex are close in meaning, complicated applies to what offers great difficulty in understanding, solving, or explaining.

complicated legal procedures

When might intricate be a better fit than complex?

The synonyms intricate and complex are sometimes interchangeable, but intricate suggests such interlacing of parts as to make it nearly impossible to follow or grasp them separately.

an intricate web of deceit

When is it sensible to use involved instead of complex?

Although the words involved and complex have much in common, involved implies extreme complication and often disorder.

a rambling, involved explanation

When would knotty be a good substitute for complex?

While in some cases nearly identical to complex, knotty suggests complication and entanglement that make solution or understanding improbable.

knotty ethical questions

How does the adjective complex differ from other similar words?

Some common synonyms of complex are complicated, intricate, involved, and knotty. While all these words mean "having confusingly interrelated parts," complex suggests the unavoidable result of a necessary combining and does not imply a fault or failure.

a complex recipe

When is complicated a more appropriate choice than complex?

While the synonyms complicated and complex are close in meaning, complicated applies to what offers great difficulty in understanding, solving, or explaining.

complicated legal procedures

When might intricate be a better fit than complex?

The synonyms intricate and complex are sometimes interchangeable, but intricate suggests such interlacing of parts as to make it nearly impossible to follow or grasp them separately.

an intricate web of deceit

When is it sensible to use involved instead of complex?

Although the words involved and complex have much in common, involved implies extreme complication and often disorder.

a rambling, involved explanation

When would knotty be a good substitute for complex?

While in some cases nearly identical to complex, knotty suggests complication and entanglement that make solution or understanding improbable.

knotty ethical questions

Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Recent Examples of complex
Adjective
To that end, Interspare’s Krantz K30 stenter is designed to handle complex materials, maintain consistent drying and reduce energy use. Alexandra Harrell, Footwear News, 10 Apr. 2026 The Daily Money breaks down complex consumer and financial news. Daniel De Visé, USA Today, 10 Apr. 2026
Noun
The district, which includes a 1,300-acre park complex and was organized in 1902, is known for its Mineral Springs Park, golf courses and hiking trails, among other facilities. Bloomberg, Chicago Tribune, 15 Apr. 2026 Outfielder Alex Verdugo, who signed a minor league deal with the Padres late in spring training, is tending to a sore throwing shoulder at the Padres spring training complex in Peoria, Ariz. Jeff Sanders, San Diego Union-Tribune, 15 Apr. 2026 See All Example Sentences for complex
Recent Examples of Synonyms for complex
Adjective
  • The figures had cracked in many places and some of the statues revealed their complicated armature.
    Douglas Stuart, New Yorker, 12 Apr. 2026
  • Legacy therapeutic approaches are sometimes complicated, costly, slow or restricted in geography.
    Lucy Jones April 11, Miami Herald, 11 Apr. 2026
Adjective
  • The mandolins weave intricate patterns together, in counterpoint or unison.
    Tim Parks, New Yorker, 11 Apr. 2026
  • All the intricate meetings and rolling knolls, all the reliable critiques of the kids today, have left this former student in the ranking spirit.
    Brittany Allen, Literary Hub, 10 Apr. 2026
Noun
  • Ukrainian drones targeted an industrial facility in Sterlitamak, a Russian city about 1,300 kilometers (roughly 800 miles) east of the border with Ukraine, local authorities said.
    ABC News, ABC News, 15 Apr. 2026
  • After the flight crew allegedly requested an onboard doctor, a physician-passenger advised that due to the severity of the burns and their proximity to her genitals, AC should be transported to an urgent care facility as soon as possible, the complaint says.
    Colson Thayer, PEOPLE, 15 Apr. 2026
Noun
  • The Army’s policy at the time of the crash mandated that its helicopters fly without that system on to conceal their locations, although the helicopter involved in this crash was on a training flight, not a sensitive mission.
    ABC News, ABC News, 14 Apr. 2026
  • Malone says a gas collection and control system runs $4 to 6 million.
    Shaun Boyd, CBS News, 14 Apr. 2026
Verb
  • The Middle East conflict has complicated the Fed's rate-setting approach, as the central bank weighs the lasting price impact of the energy shock.
    Sarah Min,Sean Conlon,Hugh Leask, CNBC, 10 Apr. 2026
  • The science fiction New Wave of the 60s and 70s complicated Gernsback’s notion about the proper relationship between science and literature and in the process produced something new and valuable.
    Literary Hub, Literary Hub, 10 Apr. 2026
Adjective
  • Born from the embers of the eighties band Talulah Gosh, Heavenly, led by the singer and guitarist Amelia Fletcher, shuffled forward with her riffy, effervescent playing style, gradually growing more sophisticated across four LPs and an EP, without any loss of buoyancy.
    Hilton Als, New Yorker, 10 Apr. 2026
  • Analysts say the groups are secretly cooperating with Iran’s government despite public claims of independence, using sophisticated bandwidth to spread content across restricted networks.
    Sam McNeil, Los Angeles Times, 10 Apr. 2026
Adjective
  • Police were unable to provide a detailed description of the suspects, but described them as two African American men between 20 and 30 years of age.
    Jeramie Bizzle, CBS News, 12 Apr. 2026
  • The astronauts obliged, returning detailed observations of Orientale.
    Mike Wall, Space.com, 11 Apr. 2026
Noun
  • Social capital is the strength of relationships within a network and the value those relationships create.
    Monica L. Wang, STAT, 10 Apr. 2026
  • In 2024, CesiumAstro landed a contract with NASA to develop advanced radio to support ground testing of navigation networks.
    Brandon Lingle, Austin American Statesman, 10 Apr. 2026

Browse Nearby Words

Cite this Entry

“Complex.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/complex. Accessed 17 Apr. 2026.

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