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
Meanwhile, production cannot easily keep pace, and many advanced munitions rely on complex supply chains and specialized components. James Laporta, CBS News, 24 Apr. 2026 These markers could be as simple as a grid of dots on the outside of the window or as complex as ultraviolet coatings that birds can see but humans can’t. K. R. Callaway, Scientific American, 24 Apr. 2026
Noun
The outdoor complex has seen several new tenants announced or opening, including Crate & Barrel which is expected to open close to Independence Day, Ascension Coffee Roastery slated to open sometime in August and Rothy’s, which recently opened near Vuori and across from Tecovas. Fousia Abdullahi, Fort Worth Star-Telegram, 29 Apr. 2026 For decades, the unfixable Rikers Island has hurt New Yorkers — those inside the massive complex’s walls and all of us beyond them. Jonathan Lippman, New York Daily News, 29 Apr. 2026 See All Example Sentences for complex
Recent Examples of Synonyms for complex
Adjective
  • But there are other factors that make calculating the distance of future Artemis missions a little complicated.
    Stephen Clark, ArsTechnica, 25 Apr. 2026
  • Considering the lack of answers from the private lab, Moore believes the hair sample is rootless, which makes identification way more complicated.
    Lizzie Lanuza, StyleCaster, 25 Apr. 2026
Adjective
  • As many clubs in the lower leagues look to ape the intricate build-up popularised by elite managers such as Pep Guardiola, have Bromley just demonstrated that long-ball football still works?
    Anantaajith Raghuraman, New York Times, 23 Apr. 2026
  • Though often dismissed as bubblegum soul, the early Jackson 5 hits were intricate and infectious.
    Andy Greene, Rolling Stone, 23 Apr. 2026
Noun
  • The documents go on to say that after Dukes was arrested and placed into a Chicago youth facility at 15 years old, he was signed to Warner Records.
    Tess Kenny, Chicago Tribune, 29 Apr. 2026
  • The planned International Drive attraction, which has never opened, came under fire after state reports of 31 sloth deaths in a warehouse facility more than a year ago.
    Dewayne Bevil, The Orlando Sentinel, 28 Apr. 2026
Noun
  • State-of-the-art drones, and the technology needed to intercept them, have become as important to national weapons arsenals as missiles, Patriot systems, fighter jets, and warships.
    Sudarsan Raghavan, New Yorker, 28 Apr. 2026
  • Over the past decade, research has consistently shown that natural fibers like cotton can biodegrade across a wide range of environments, including freshwater, saltwater, wastewater systems, soil, and compost.
    Angela Velasquez, Footwear News, 27 Apr. 2026
Verb
  • Concerns about the injury complicated his evaluation.
    Jeff Howe, New York Times, 25 Apr. 2026
  • This year that quarterback-in-waiting is Alabama’s Ty Simpson, a talented and smart player whose evaluation is complicated by injury struggles, as well as a lack of starting experience and consistency.
    Andrew Greif, NBC news, 24 Apr. 2026
Adjective
  • The series’ earnestly naïve sound design (horses neighing, cars revving) only enhanced my appreciation of Joudrey’s sophisticated storytelling.
    Sheldon Pearce, New Yorker, 24 Apr. 2026
  • Ditto the sophisticated modulations and subtle rhythmic shifts that underpin Puth’s best songs.
    George Varga, San Diego Union-Tribune, 24 Apr. 2026
Adjective
  • Scammers can repeat this process hundreds of times a day, building detailed profiles with very little effort.
    Kurt Knutsson, FOXNews.com, 25 Apr. 2026
  • The board approved the plan, but also is seeking a more detailed delineation of the affordable housing elements.
    Staff Report, Hartford Courant, 25 Apr. 2026
Noun
  • Tong referenced an expose on CNN that revealed a network of websites and group chats on platforms like Telegram in which men uploaded videos of drugging and raping their wives and advised others how to do the same.
    Emilia Otte, Hartford Courant, 24 Apr. 2026
  • During the event, Vietnam’s deputy minister of industry and trade, Nguyen Sinh Nhat Tan, highlighted how FedEx’s global footprint would complement Viettel Post’s domestic network to ultimately enhance Vietnam’s ability to scale exports worldwide.
    Glenn Taylor, Footwear News, 24 Apr. 2026

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Cite this Entry

“Complex.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/complex. Accessed 1 May. 2026.

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