complex 1 of 3

adjective

käm-ˈpleks How to pronounce complex (audio)
Definition of complexnext
1
as in complicated
having many parts or aspects that are usually interrelated this medical device is a complex instrument that requires careful handling complex issues regarding free speech and school discipline

Synonyms & Similar Words

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Antonyms & Near Antonyms
2
as in intricate
made or done with great care or with much detail a complex plan for evacuating the city in the event of a natural disaster

Synonyms & Similar Words

Antonyms & Near Antonyms

complex

2 of 3

noun

ˈkäm-ˌpleks How to pronounce complex (audio)
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

käm-ˈpleks How to pronounce complex (audio)
as in to complicate
to make complex or difficult there's no need to complex what should be a simple process for obtaining a building permit

Synonyms & Similar Words

Antonyms & Near Antonyms

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complex systems
large systems
large-scale systems
hard systems
advanced systems
complex problems
intricate problems
tough problems
sophistical problems
convoluted problems
confusing problems
a complex structure
a difficult structure
a complicated structure
a detailed structure
a large structure
an elaborate structure
complex interactions
sophisticated interactions
detailed interactions
deep interactions
multiple interactions
several interactions
a complex process
a hard process
a long process
a massive process
an involved process
a huge process

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
Myers led the complex negotiations, finalizing the largest section of the deal in 2000 at a cost of $30 million in conservancy funds and $15 million from federal sources. —Elaine Woo, Los Angeles Times, 11 Mar. 2025 There, he was first diagnosed with a complex viral, bacterial and fungal respiratory tract infection. —Andrea Margolis, Fox News, 10 Mar. 2025
Noun
The complex, in the 18th and Vine Jazz District, faced high vacancy rates and poor conditions in some units in recent years, and community leaders have pushed to find a way forward. —Chris Higgins, Kansas City Star, 8 Mar. 2025 The term nonprofit industrial complex (NPIC) is a takeoff on references to the military industrial complex. —David Plymyer, Baltimore Sun, 8 Mar. 2025 See All Example Sentences for complex
Recent Examples of Synonyms for complex
  1. complicated
  2. intricate
  3. facility
  4. system
  5. complicate
  6. sophisticated
  7. detailed
  8. network
Adjective
  • Some of this ‘fresh stock’ is explained by such properties having hit an ancestral dead-end: many villas have been handed down through local families for generations and some are now owned by multiple grandchildren who would prefer to sell than manage a complicated ‘who stays when’ calendar.
    — Lysanne Currie, Forbes, 11 Mar. 2025
  • Carell and Horgan’s HBO series Set on a college campus, the untitled Steve Carell comedy from Lawrence and Matt Tarses, which is slated to start production next month, centers on an author’s (Carell) complicated relationship with his daughter.
    — Nellie Andreeva, Deadline, 10 Mar. 2025
Definition of complicated
Adjective
  • Where the Rubik's Cube is solved by twisting blocky columns in intricate patterns and sequences, the Magic Cube design is a much simpler proposition.
    — Paul Ridden, New Atlas, 14 Mar. 2025
  • Some, like Martin’s idol and inspiration, J.R.R. Tolkien, are architects, meticulously planning out their intricate worlds and the hundreds of characters and story lines that exist within them.
    — Sean T. Collins, Vulture, 13 Mar. 2025
Definition of intricate
Noun
  • But the prospect of higher prices, fewer sales and lower profits might cause some companies to refrain from investing in new facilities.
    — arkansasonline.com, arkansasonline.com, 13 Mar. 2025
  • The Jena, Louisiana facility where he is currently held has been the subject of multiple allegations of human rights violations, including lack of medical care, physical abuse, and prolonged solitary confinement.
    — Andy J. Semotiuk, Forbes, 13 Mar. 2025
Definition of facility
Noun
  • The big picture: The fires that have razed at least 170,000 acres ignited Friday are tied to the same giant storm system that brought tornadoes to the U.S. South, per Axios' Andrew Freedman.
    — Rebecca Falconer, Axios, 17 Mar. 2025
  • Macroeconomic Uncertainty Last but certainly not least is the continued and apparently increasing macroeconomic uncertainty that continues to permeate the U.S. economy – and by extension – the global financial system.
    — Sean Stein Smith, Forbes, 16 Mar. 2025
Definition of system
Verb
  • That’s the one thing that could get complicated, at least from a hitter’s perspective.
    — LaMond Pope, Chicago Tribune, 10 Mar. 2025
  • Figuring out the best time to apply can be complicated.
    — Liz Weston, Los Angeles Times, 9 Mar. 2025
Definition of complicate
Adjective
  • One sophisticated take on the trend turns the clog into a main character by combining it with matching neutral tones for a refined air.
    — Casandra Maggio, Glamour, 12 Mar. 2025
  • Honda claims that the S7, its first-ever premium electric SUV, will break new ground thanks to exceptional comfort, a sophisticated modern look, and, most importantly, more than 400 miles (650 km) of driving range.
    — New Atlas, New Atlas, 12 Mar. 2025
Definition of sophisticated
Adjective
  • Other strikers were floated by members of the recruitment team but, after poring over footage and receiving detailed feedback, Howe became transfixed.
    — Chris Waugh, The Athletic, 14 Mar. 2025
  • An early estimate pegged the cost at $12 million to design and construct, of which the city would contribute $7.5 million, but no detailed design or construction pan has yet been prepared.
    — Stephen Hudak, Orlando Sentinel, 13 Mar. 2025
Definition of detailed
Noun
  • By leveraging our exclusive data and network, JOOR Discover fosters stronger introductions that build trust and translate into lasting business relationships.
    — Fairchild Studio, WWD, 18 Mar. 2025
  • The network’s news division was the most impacted by a round of layoffs at The Walt Disney Co. earlier this month.
    — Ted Johnson, Deadline, 18 Mar. 2025
Definition of network

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Cite this Entry

“Complex.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/complex. Accessed 23 Mar. 2025.

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More from Merriam-Webster on complex

Nglish: Translation of complex for Spanish Speakers

Britannica.com: Encyclopedia article about complex

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