complex

noun
com·​plex | \ ˈkäm-ˌpleks How to pronounce complex (audio) \

Definition of complex

 (Entry 1 of 3)

1 : a whole made up of complicated or interrelated parts a complex of welfare programs the military-industrial complex
2a : a group of culture traits relating to a single activity (such as hunting), process (such as use of flint), or culture unit
b(1) : a group of repressed desires and memories that exerts a dominating influence upon the personality a guilt complex
(2) : an exaggerated reaction to or preoccupation with a subject or situation He has always had a complex about spiders. She has a weight complex. Not being able to find a job was giving me a complex.
c : a group of obviously related units of which the degree and nature of the relationship is imperfectly known
d : the sum of factors (such as symptoms) characterizing a disease or condition primary tuberculous complex
3 : a chemical association of two or more species (such as ions or molecules) joined usually by weak electrostatic bonds rather than covalent bonds
4 : a building or group of buildings housing related units an apartment complex a sports complex

complex

adjective
com·​plex | \ käm-ˈpleks How to pronounce complex (audio) , kəm-ˈpleks, ˈkäm-ˌpleks \

Definition of complex (Entry 2 of 3)

1a : composed of two or more parts : composite a complex mixture of chemicals
b(1) of a word : having a bound form as one or more of its immediate constituents Unmanly is a complex word.
(2) of a sentence : consisting of a main clause and one or more subordinate clauses
2 : hard to separate, analyze, or solve a complex problem
3 : of, concerned with, being, or containing complex numbers a complex root complex analysis

complex

verb
com·​plex | \ käm-ˈpleks How to pronounce complex (audio) , kəm-ˈpleks, ˈkäm-ˌpleks \
complexed; complexing; complexes

Definition of complex (Entry 3 of 3)

transitive verb

1 : to make complex or into a complex

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Other Words from complex

Adjective

complexly adverb
complexness noun

Verb

complexation \ ˌkäm-​ˌplek-​ˈsā-​shən How to pronounce complexation (audio) , kəm-​ \ noun

Choose the Right Synonym for complex

Adjective

complex, complicated, intricate, involved, knotty 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 complicated applies to what offers great difficulty in understanding, solving, or explaining. complicated legal procedures intricate suggests such interlacing of parts as to make it nearly impossible to follow or grasp them separately. an intricate web of deceit involved implies extreme complication and often disorder. a rambling, involved explanation knotty suggests complication and entanglement that make solution or understanding improbable. knotty ethical questions

The Complex Origins of Complex

The word complex lives up to its name, as it contains multiple parts of speech and senses. It serves as an adjective, a noun, and, less commonly, as a verb. The verb use is the oldest of the three, with an original meaning of “to join or unite.” Complex comes from the Latin complecti, which means “to entwine around, to embrace,” a word that is based in part on plectere (“to braid”). English has a number of other words that can be traced to plectere, including perplex, plexus (“an intricately interwoven combination of elements or parts in a cohering structure”), and amplexus (“the mating embrace of some amphibians, such as frogs and toads”).

Examples of complex in a Sentence

Noun She has a complex about her appearance. a complex of protein molecules Adjective The house's wiring is complex. The situation is more complex than you realize. Verb there's no need to complex what should be a simple process for obtaining a building permit
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Recent Examples on the Web: Noun Of the 58 new cases the county reported on Sunday, 56 were associated with the federal prison complex in Lompoc, officials said. Los Angeles Times, "California’s coronavirus outlook worse than researchers expected, as cases and deaths rise," 11 May 2020 The other two gardens which are located in sports complexes, Alden Bridge and Bear Branch, community garden members went from one garden slot that they were permitted to access the gardens per week to now four slots. Jeff Forward, Houston Chronicle, "Woodlands gardeners get expanded access to community garden plots," 11 May 2020 Check The company is currently leading a group looking to build a zero-carbon cluster at the U.K.’s Teesside industrial complex, which includes oil refineries and chemical factories. Akshat Rathi, Bloomberg.com, "BP Beefs Up Carbon Capture Team in Bid to Meet Climate Goals," 8 May 2020 Hours after that shooting, police say officers were called to a burglary in progress at an apartment complex, where a man ambushed them, opening fire with a rifle. Rebekah Riess, CNN, "Indianapolis enlists independent oversight after protests over officer-involved shootings," 8 May 2020 In Wilson’s apartment complex, residents had tied colorful, congratulatory signs on balconies and were watching from above. Vincent T. Davis, ExpressNews.com, "San Antonio senior living community surprises woman on 105th birthday with parade, outdoor festivities," 3 May 2020 In any case, the imaging technique requires taking thousands of electron micrographs of individual protein-RNA-drug complexes, all of them oriented randomly. John Timmer, Ars Technica, "First drug known to work against SARS-CoV-2 imaged in action," 1 May 2020 For the past several weeks, Beaver Creek has been crawling with construction workers renovating the complex, leaving construction debris, including nails and wood scattered about. Cary Spivak, Milwaukee Journal Sentinel, "COVID-19 doesn't stop Berrada workers from replacing windows, doors in occupied apartments," 30 Apr. 2020 Farmers Fridge's 400 machines are located at airports, college campuses, office complexes, and hospitals. Margaret Littman, Fortune, "Vending machines—the original contactless delivery systems—now deliver ramen and art to U.S. consumers," 25 Apr. 2020 Recent Examples on the Web: Adjective The court found that the Evers administration must follow a complex rulemaking process to put his plans in place. USA TODAY, "Wisconsin lawmakers say counties and cities are on their own after court ruling in coronavirus case," 14 May 2020 Getty Images Making ice cream at home feels like alchemy, a complex process of mixing and cooling. Amelia Nierenberg, New York Times, "Basic Mason Jar Ice Cream," 9 May 2020 It was developed mainly for this reason: Some cases are too complex, too adversarial, for the customary peer-review process. Gregg Doyel, Indianapolis Star, "Doyel: NCAA's new independent infractions structure is complicated and terrifying," 2 May 2020 Because the processing is taking place in a device separate from the headset itself, the experience can be much more complex and intricate, giving it better imaging and spatial movement. Gabrielle Hondorp, Popular Mechanics, "The 5 Best VR Headsets for Immersive Gaming," 1 May 2020 The script is more complex than some of the initial reviews gave it credit for being, but the message comes through loud and clear. Michael Brendan Dougherty, National Review, "A Golden Age for Right-Wing Content on Streaming Services," 29 Apr. 2020 Immunity from the virus may be a more complex process than expected. Ari Altstedter, Fortune, "Why scientists are touting coronavirus ‘herd immunity’ for India when it didn’t work for the U.K.," 22 Apr. 2020 Lifting shelter-in-place restrictions and reopening society is a complex process that could take weeks to unfold, public health experts have said. Erin Allday, SFChronicle.com, "California’s coronavirus reopening: Gov. Gavin Newsom spells out six criteria," 14 Apr. 2020 Some cases are long unsolved, others too complex, high-profile or sensitive for local departments to handle alone. Dallas Morning News, "Texas law enforcement uses hypnosis to investigate crimes. Does it uncover the truth?," 8 Apr. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'complex.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of complex

Noun

1643, in the meaning defined at sense 1

Adjective

1645, in the meaning defined at sense 1a

Verb

1658, in the meaning defined at sense 1

History and Etymology for complex

Noun

Late Latin complexus totality, from Latin, embrace, from complecti — see complex entry 2

Adjective

Latin complexus, past participle of complecti to embrace, comprise (a multitude of objects), from com- + plectere to braid — more at ply

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Time Traveler for complex

Time Traveler

The first known use of complex was in 1643

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Statistics for complex

Last Updated

17 May 2020

Cite this Entry

“Complex.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/complex. Accessed 28 May. 2020.

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More Definitions for complex

complex

noun
How to pronounce complex (audio)

English Language Learners Definition of complex

 (Entry 1 of 2)

: a group of buildings, apartments, etc., that are located near each other and used for a particular purpose
: an emotional problem that causes someone to think or worry too much about something
: a group of things that are connected in complicated ways

complex

adjective
How to pronounce complex (audio)

English Language Learners Definition of complex (Entry 2 of 2)

: having parts that connect or go together in complicated ways
: not easy to understand or explain : not simple
grammar : consisting of a main clause and one or more additional clauses

complex

adjective
com·​plex | \ käm-ˈpleks How to pronounce complex (audio) , kəm-ˈpleks, ˈkäm-ˌpleks \

Kids Definition of complex

1 : not easy to understand or explain : not simple complex instructions
2 : having parts that go together in complicated ways a complex invention

complex

adjective
com·​plex | \ käm-ˈpleks How to pronounce complex (audio) , kəm-ˈ How to pronounce complex (audio) , ˈkäm-ˌ \

Medical Definition of complex

 (Entry 1 of 3)

1 : having many varied interrelated parts, patterns, or elements and consequently hard to understand complex behavior a complex personality complex plants and animals
2 : formed by the union of simpler chemical substances complex proteins

complex

noun
com·​plex | \ ˈkäm-ˌpleks How to pronounce complex (audio) \

Medical Definition of complex (Entry 2 of 3)

1 : a group of repressed memories, desires, and ideas that exert a dominant influence on the personality and behavior a guilt complex — see castration complex, electra complex, inferiority complex, oedipus complex, persecution complex, superiority complex
2 : a group of chromosomes arranged or behaving in a particular way — see gene complex
3 : a chemical association of two or more species (as ions or molecules) joined usually by weak electrostatic bonds rather than by covalent bonds
4 : the sum of the factors (as symptoms and lesions) characterizing a disease primary tuberculous complex
com·​plex | \ käm-ˈpleks How to pronounce complex (audio) , kəm-ˈ How to pronounce complex (audio) , ˈkäm-ˌ \

Medical Definition of complex (Entry 3 of 3)

1 : to form into a complex RNA complexed with protein

intransitive verb

: to form a complex hormones which must complex with specific receptors

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Comments on complex

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