Definition of complexnext
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

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

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
But the firm had little expertise in the complex area of immigration law. Ruth Marcus, New Yorker, 15 Aug. 2026 At Panchenko, Altima’s source for roe, that’s because the final product is the result of a complex, ongoing cultivation process. Felipe Riccio, Robb Report, 15 Aug. 2026
Noun
New Orleans had no scuffles or disciplinary issues Thursday during another joint practice with the Rams at Los Angeles' training complex in Woodland Hills. ABC News, 20 Aug. 2026 Ulysses works with a third-party property management company to help run its complexes, but some residents require extra care and attention that the developer wants to provide itself. Matthew Geiger, Denver Post, 20 Aug. 2026 See All Example Sentences for complex
Recent Examples of Synonyms for complex
Adjective
  • There’s a recent example of how complicated that can be in practice.
    Elisabeth Buchwald, CNN Money, 17 Aug. 2026
  • Finding the balance between preserving clubhouse culture and throwing future pieces into the fire remains complicated, even as the team dropped to 60-65 following Saturday’s 5-4 walk-off loss to the New York Mets.
    Spencer Nusbaum, New York Times, 16 Aug. 2026
Adjective
  • Bridges and overhangs were clean, confirming excellent exposure calibration and the printer's ability to resolve intricate features without sacrificing dimensional accuracy.
    Michael Lydick, PC Magazine, 21 Aug. 2026
  • Those jurisdictional questions look to set up a pretty intricate set of arguments before the judge gets to the merits of the case.
    Ted Johnson, Deadline, 21 Aug. 2026
Noun
  • The system, developed to protect airbases and other military facilities, cannot currently detect or jam some frequencies used by newer Chinese drones and has limited protection against emerging threats.
    Bojan Stojkovski, Interesting Engineering, 16 Aug. 2026
  • Ukrainian forces also again targeted facilities belonging to Russia's e-commerce giant Wildberries.
    David Brennan, ABC News, 16 Aug. 2026
Noun
  • Cyber Surveillance Operations discreetly collect information and intelligence and involve unauthorized access of information systems.
    Jill Goldenziel, Forbes.com, 19 Aug. 2026
  • Modular systems extend aircraft life A key part of the modernization is the use of commercial off-the-shelf technology.
    Neetika Walter, Interesting Engineering, 19 Aug. 2026
Verb
  • The death sentence complicates any extradition under Russian law, but a decision not to hand over a former close ally to face justice would be far more political than legal, experts say.
    Paula Hancocks, CNN Money, 16 Aug. 2026
  • While the White House hoped to remove Díaz-Canel and the Castro family from power, the push has been complicated by the lack of a credible opposition since revolutionary brothers Fidel and Raúl overthrew the island’s military dictatorship in 1959.
    Bloomberg, Chicago Tribune, 15 Aug. 2026
Adjective
  • Something Sculptural As the name would suggest, the Rodin stool from Arhaus has a sculptural appeal—it can be easily assimilated into a sophisticated bar setup, or used to dress up a more casual breakfast bar.
    Kelly Dawson, Architectural Digest, 17 Aug. 2026
  • In Chicago, perpetrators are a mix of opportunists and more sophisticated networks often tied to street gangs.
    Kiel Porter, Fortune, 17 Aug. 2026
Adjective
  • That could change an early stage of mineral exploration, where companies must decide where to spend money collecting more detailed data and drilling test wells.
    Neetika Walter, Interesting Engineering, 20 Aug. 2026
  • OpenAI’s detailed, self-critical account of pausing its own model functions as a claim to that same safety-conscious ground, whether or not that was the intent behind it.
    Ashish Bhatia, Forbes.com, 19 Aug. 2026
Noun
  • One of the biggest inefficiencies keeping electricity costs high lies in the distribution network itself, Manga said.
    ABC News, ABC News, 19 Aug. 2026
  • Bezos, who stepped down as CEO five years ago, pledged in 2013 to build a network of drones to deliver small packages in 30 minutes or less.
    Annie Palmer, CNBC, 19 Aug. 2026

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Cite this Entry

“Complex.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/complex. Accessed 22 Aug. 2026.

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