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
This potential value is why nuclear waste storage is so complex. David Szondy august 22, New Atlas, 22 Aug. 2026 Tributes poured in for Wright over the weekend, highlighting his masterful performances playing often wounded, complex characters. Marlene Lenthang, NBC news, 22 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
  • Some 400 firefighters have been battling the blaze, aided by helicopters flying overnight, officials said, but high winds had complicated efforts to contain it.
    Martin Goillandeau, CNN Money, 23 Aug. 2026
  • But deciding what to do with that money has become more complicated because cash itself is once again producing a meaningful return.
    Robert Daugherty, Forbes.com, 23 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 Russian president said those logistics facilities would be built back with government support.
    Nathan Hodge, CNN Money, 23 Aug. 2026
  • Glutathione is processed in sterile compounding pharmacies, and there have been cases of people getting poisoned due to contamination at these facilities, Sack said.
    ABC News, ABC News, 23 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
  • Finding a job has rarely been easy, but in 2026, fierce competition, the growing use of artificial intelligence and a lack of trust in employers have further complicated the process.
    Rachel Barber, USA Today, 21 Aug. 2026
  • The details of the investigation are complicated, to say the least, but the short version is that two companies Walter controls, both insurance companies, used investor funds on private-credit deals, essentially making loans directly to businesses.
    Ian Miller OutKick, FOXNews.com, 21 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 25 Aug. 2026.

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