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
This allows for complex maneuvers and speed adjustments that solid rockets simply can’t match. Mrigakshi Dixit, Interesting Engineering, 13 Mar. 2026 Moreover, Europe’s diversity, strong institutions, and commitment to rule of law can become competitive features in a world increasingly shaped by trust, security, and complex societal deployment. François Candelon, Fortune, 13 Mar. 2026
Noun
Terrace at Oak Springs is one of two Integral Care housing complexes. Nicole Villalpando, Austin American Statesman, 11 Mar. 2026 Soon, Kenna has moved into a shitty apartment complex (ironically called Paradise), found a job at a local market, and even made some friends (including young Monika Myers as both neighbor and coworker, and country music star Lainey Wilson, not playing herself in the film). Kate Erbland, IndieWire, 11 Mar. 2026 See All Example Sentences for complex
Recent Examples of Synonyms for complex
Adjective
  • The attacks have, however, complicated peace efforts in the region where mass graves were recently found.
    OPE ADETAYO, Arkansas Online, 15 Mar. 2026
  • The more complicated the process feels, the more likely people are to give up halfway through.
    Kurt Knutsson, FOXNews.com, 14 Mar. 2026
Adjective
  • What beautiful, intricate humanity.
    Scott Feinberg, HollywoodReporter, 13 Mar. 2026
  • Watch young John Early, Kate Berlant, and Cole Escola re-create a scene from the film in intricate detail and see camp interpretation at its finest — comedians using Showgirls’s eccentricities to unearth something delicious.
    Jason P. Frank, Vulture, 12 Mar. 2026
Noun
  • Feik said the two cubs are healthy and will be relocated to a facility before being moved into wildland areas.
    Matthew Rodriguez, CBS News, 18 Mar. 2026
  • Recent incidents included a drone attack on the world’s largest ultra-sour gas facility, a fire at the Fujairah Oil Industry Zone, and damage to a tanker near the Strait of Hormuz.
    Lee Ying Shan, CNBC, 18 Mar. 2026
Noun
  • Driving through deep water can also negatively affect a vehicle's mechanical and electrical systems.
    NC Weather Bot, Charlotte Observer, 17 Mar. 2026
  • Salvadoran nationals who were deported from the United States have been arbitrarily detained in El Salvador and have disappeared into the Central American nation's prison system, according to a Human Rights Watch report released on Monday.
    CBS News, CBS News, 17 Mar. 2026
Verb
  • Their departures illustrate just how complicated the entire roster equation is, and perhaps how availability could outweigh the desire for name-power in future configurations.
    Johnny Flores Jr, New York Times, 13 Mar. 2026
  • That calculus is complicated by the festival’s famously dense schedule.
    Ana Gutierrez, Austin American Statesman, 13 Mar. 2026
Adjective
  • Instead, The Standard, Ibiza, presents itself as a bolthole for an in-the-know, sophisticated, and louche crowd that wants a bit of buzz but without any over-the-top hoopla.
    Condé Nast, Condé Nast Traveler, 14 Mar. 2026
  • Featuring an eye-catching geometric border in beige against a dark brown base, the rug offers a sophisticated look with a sleek edge that enhances your decor and furnishings.
    Alicia Geigel, Southern Living, 13 Mar. 2026
Adjective
  • The attorneys on Thursday referenced a new report from LAist that detailed concerns from a whistleblower about who was in charge of the county’s emergency operation center, or EOC, the night of the fire.
    Rebecca Ellis, Los Angeles Times, 14 Mar. 2026
  • The agency now wants detailed doctor’s notes for every day an employee calls in sick.
    Alexandra Skores, CNN Money, 14 Mar. 2026
Noun
  • By improving detection capabilities against drone swarms, the technology could strengthen air-defense networks and reduce vulnerabilities created by rapidly evolving drone warfare tactics.
    Prabhat Ranjan Mishra, Interesting Engineering, 14 Mar. 2026
  • Over the course of his lengthy career, Anastos spent time on-air with several different flagship New York television networks, starting with ABC 7 in 1978.
    Jessica Schladebeck, New York Daily News, 13 Mar. 2026

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Cite this Entry

“Complex.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/complex. Accessed 19 Mar. 2026.

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