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
Under Israel’s complex state film funding system, the budget for cinema, which currently comes in at around 130m Israeli Shekels ($42m), is divided between six funds. Melanie Goodfellow, Deadline, 17 Sep. 2026 Her murder binge doesn’t feel ethically complex; her homicidal ventures are just nefarious. Literary Hub, 17 Sep. 2026
Noun
Russia’s Defense Ministry said the military hit metallurgical and electronics plants, factories of the military-industrial complex and energy and transport facilities. ABC News, 17 Sep. 2026 Charlotte police had shot and killed a man — a Black man, Keith Lamont Scott — outside an apartment complex that Winston regularly passed on his way home. Théoden Janes, Charlotte Observer, 17 Sep. 2026 See All Example Sentences for complex
Recent Examples of Synonyms for complex
Adjective
  • John’s café rendezvous with equally complicated father-figure Hal ends with him punching the hotshot pilot in the face, in what turns out to be an ugly goodbye.
    Siddhant Adlakha, Vulture, 21 Sep. 2026
  • The latest exercises demonstrated the basic training needed to operate the new tank so crews could progress to more complicated battlefield conditions, including environments with extensive drone disruption.
    Maria Mocerino, Interesting Engineering, 20 Sep. 2026
Adjective
  • The works on display depict his intricate captivation with the relationship between humankind and nature.
    Tianwei Zhang, Footwear News, 18 Sep. 2026
  • Its graceful design is meant to celebrate the intricate beauty of the natural world.
    Bryan Hood, Robb Report, 18 Sep. 2026
Noun
  • In February, a little more than a month after his release in Clay County, Indiana, Cazares was back at an ICE facility.
    Andrew Carter, Chicago Tribune, 20 Sep. 2026
  • The confrontation began Friday after a suicide bomber rammed an explosives-laden vehicle into a mosque, and gunmen stormed the facility, killing 21 people and wounding 103 others.
    Arkansas Online, Arkansas Online, 20 Sep. 2026
Noun
  • The study has important limitations Rare earth elements are increasingly important to industries ranging from electronics and renewable energy to advanced defense systems.
    Bojan Stojkovski, Interesting Engineering, 21 Sep. 2026
  • The delay again has created a potential cash crunch for districts during the wait for their cut — often a main revenue source for local governments — and added to the pile of complaints about the county’s decade-long property tax system upgrade.
    A.D. Quig, Chicago Tribune, 20 Sep. 2026
Verb
  • The war in the Middle East has complicated maritime shipments, forcing equipment, which countries are required to bring with them, to be airlifted at significant costs.
    Jacqueline Charles, Miami Herald, 19 Sep. 2026
  • Democratic lawmakers have raised concerns that the 260-foot arch would further complicate an already complex airspace, where just a year and a half ago, the deadliest plane crash on American soil since 2009 occurred.
    Sarah Ploss, CBS News, 18 Sep. 2026
Adjective
  • The systems are among the most sophisticated industrial machines ever built and are critical to modern leading-edge chip production.
    Bojan Stojkovski, Interesting Engineering, 19 Sep. 2026
  • Regular, petite, and plus While many shackets read rugged and outdoorsy, this one feels sleek and sophisticated enough for the office or a nice dinner.
    Alison Syrett Cleary, InStyle, 18 Sep. 2026
Adjective
  • His book is filled with detailed accounts of patients who responded in different ways to their diagnosis.
    Steve Lopez, Los Angeles Times, 23 Sep. 2026
  • Taaffe’s diligence, intelligence, understanding of the position (beyond his years) and detailed preparation have earned him the trust of coach Jeff Hafley.
    Barry Jackson, Miami Herald, 23 Sep. 2026
Noun
  • White House reporters from the two cable networks -- Betsy Klein of CNN and Akayla Gardner of MS NOW -- both went live to report they'd been turned away, their press badges deactivated, when arriving for their jobs at the White House.
    Arkansas Online, Arkansas Online, 20 Sep. 2026
  • The case was sparked by a nearly $800 million settlement Fox paid to Dominion Voting Systems, which accused the network of spreading conspiracy theories about fraud in the 2020 election.
    Maddy Lauria, NPR, 20 Sep. 2026

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Cite this Entry

“Complex.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/complex. Accessed 24 Sep. 2026.

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