complex

noun
com·plex | \ˈkäm-ˌpleks \

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, 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, kəm-ˈpleks, ˈkäm-ˌpleks\
complexed; complexing; complexes

Definition of complex (Entry 3 of 3)

transitive verb

1 : to make complex or into a complex

2 : chelate

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Other Words from complex

Adjective

complexly adverb
complexness noun

Verb

complexation \ˌkäm-ˌplek-ˈsā-shən, kəm- \ noun

Synonyms & Antonyms for complex

Synonyms: Noun

network, system

Synonyms: Adjective

complicated, detailed, elaborate, fancy, intricate, involved, sophisticated

Synonyms: Verb

complexify, complicate, embarrass, entangle, perplex, sophisticate

Antonyms: Adjective

no-frills, simple, unfancy, unsophisticated

Antonyms: Verb

simplify, streamline

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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

Timmy Kinner, a 30-year-old homeless man who had briefly been a guest at the apartment complex where Ruya lived, has been charged with first-degree murder and several other felonies in connection with the attack. Rebecca Boone, chicagotribune.com, "Refugee who fled violence mourns 3-year-old daughter slain at her birthday party in Idaho," 4 July 2018 After all, most of the other units in this building, the city’s first high-rise condominium complex, have only one front door. Shari Rudavsky, Indianapolis Star, "Hot Property: 4-bedroom Tarkington Tower condo for $550K means amenities plus view," 13 July 2018 The boys became trapped in the cave after heavy rains flooded the complex. Nicole Darrah, Fox News, "Thai cave where soccer team was trapped will become a 'living museum,' official says," 12 July 2018 This not-so-mad scientist's lair is in a house not far from the public-housing complex where the musician grew up. John Defore, The Hollywood Reporter, "'Milford Graves: Full Mantis': Film Review," 11 July 2018 Soldiers unload aid supplies near the cave complex. Jake Maxwell Watts, WSJ, "The Thai Cave Rescue, Before Its Triumph, Teetered on the Brink of Disaster," 11 July 2018 The new center is expected to open in the summer of 2019 on 2 acres on Compton Road adjacent to the Cary Crossing housing complex for residents with disabilities. Jennie Key, Cincinnati.com, "City wins appeal in public records lawsuit," 12 July 2018 Beckham is trying build support for a massive sports, retail and entertainment complex that would potentially be built at Melreese Country Club, next to Miami International Airport. Emily Himes, miamiherald, "David Beckham played soccer with these kids. And he lost.," 11 July 2018 The renovation of the North Armory will bring the number of rentals at the factory complex to 177, including 129 at the South Armory. Kenneth R. Gosselin, courant.com, "Renovations Begin In Last Major Structure At Hartford's Colt Complex," 11 July 2018

Recent Examples on the Web: Adjective

Grilled lamb burgers, on the other hand, entice me with the rich, complex flavor of the meat itself. Adam Ried, BostonGlobe.com, "Recipes: Switch it up with lamb burgers instead of beef," 13 July 2018 Literature has proven a fertile source of complex female roles since the dawn of cinema, with Little Women generating its first feature moving picture adaptation in 1917. Marley Marius, Vogue, "8 Stirring Tales of Sisterhood Adapted From the Page to the Silver Screen (That Aren’t Greta Gerwig’s Little Women)," 13 July 2018 They were found 10 days later, huddled on a small, dry shelf just above the water, and divers and other international rescuers plotted the complex mission to rescue the team before more rain came. Fox News, "Mission accomplished and boys healthy, rescuers head home," 13 July 2018 But according to the data analyst, who has spent stints at Redfin and Denmark’s Gehl Architects, Philadelphia’s parking count was derived from an analysis of three complex data sets. Caitlin Mccabe, Philly.com, "Philadelphia has 2,172,896 parking spaces. So how come you're still circling the block?," 12 July 2018 Rodent pesticides that have eliminated problem mice and rats on small islands are too risky to use on larger islands, with complex ecosystems and large human populations, Packard says. Ewen Callaway, Scientific American, "Controversial CRISPR “Gene Drives” Tested in Mammals for the First Time," 10 July 2018 Beckham and his partners foresee the Miami Freedom Park complex generating $425 million a year in revenue. Craig Davis, Sun-Sentinel.com, "David Beckham, Jorge Mas encounter opposition in latest bid for Miami MLS stadium," 13 July 2018 And the fact that two different agencies are in charge of adults and children makes everything more complex. Ella Nilsen, Vox, "The Trump administration says it has reunited more than 500 families. One legal group in Texas has confirmed 4 cases.," 26 June 2018 Provider groups and some Medicaid recipients and their families have said that KanCare made the Medicaid system more complex and secretive, especially for Kansans with disabilities. Andy Marso And Jonathan Shorman, kansascity, "New contracts shake up KanCare: One insurance company out and a new one in," 22 June 2018

Recent Examples on the Web: Verb

Donofrio laments the loss of the Housing Coalition and points to another blow, citing large Johnson County complexes built in the late 1990s with low-income housing tax credits that are now expiring. Lynn Horsley, kansascity, "JoCo agency gave low-income residents a lifeline. Now it's shutting down," 1 July 2018 The housing authority has tried four times to get permission to demolish its Lake Mann Apartments complex off John Young Parkway, also hoping to rebuild that 210-unit community. Kate Santich, OrlandoSentinel.com, "Griffin Park public housing complex could face demolition, relocating 345 residents," 29 June 2018 Petrochemical giant LyondellBasell, for example, is adding to its La Porte complex a $700 million plastics plant expected to produce more than a billion pounds of polyethylene each year. Katherine Blunt, Houston Chronicle, "Houston-area petrochemical producers look overseas to sell plastic," 1 Feb. 2018 The first launch suffered a year’s worth of delays, and the shuttle sat four months on the launch complex 39 as new problems mounted. Joe Pappalardo, Popular Mechanics, "How Astronaut John Young Tamed the Space Shuttle," 8 Jan. 2018 Also, any bid would have to come with the cooperation of the Los Angeles host committee, which recently agreed to complex financial arrangements with the USOC as part of its deal to stage the games. USA TODAY, "USOC CEO to IOC on Russian doping: Time for action is now," 12 Oct. 2017 The storm complex formed under an extremely similar weather pattern to the 2012 derecho. Jason Samenow, Washington Post, "The forgotten derecho of 1954 that slammed Washington," 27 June 2017 Deer and elk have complex digestive systems and have specific dietary needs. Terry Wickstrom, The Denver Post, "Wickstrom: Colorado Parks and Wildlife initiates baiting program to move deer, elk," 31 Jan. 2017 Juan Gavalda, MD, family medicine physician on the medical staff at Methodist Mansfield Medical Center, recommends three things that will help individuals stay energized all day long: ▪ Complex carbs– Angel Biasatti, star-telegram.com, "Staying energized all day long, the healthy way," 20 June 2017

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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Statistics for complex

Last Updated

21 Sep 2018

Look-up Popularity

Time Traveler for complex

The first known use of complex was in 1643

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More Definitions for complex

complex

noun

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

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, 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, kəm-ˈ, 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 \

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

complex

transitive verb
com·plex | \käm-ˈpleks, kəm-ˈ, ˈkäm-ˌ\

Medical Definition of complex (Entry 3 of 3)

1 : to form into a complex RNA complexed with protein

2 : chelate

intransitive verb

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

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Comments on complex

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