complex

[ adjective, verb kuhm-pleks, kom-pleks; noun kom-pleks ]

/ adjective, verb kəmˈplɛks, ˈkɒm plɛks; noun ˈkɒm plɛks /

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See synonyms for: complex / complexes on Thesaurus.com

adjective

composed of many interconnected parts; compound; composite: a complex highway system.

characterized by a very complicated or involved arrangement of parts, units, etc.: complex machinery.

so complicated or intricate as to be hard to understand or deal with: a complex problem.

Grammar.

(of a word) consisting of two parts, at least one of which is a bound form, as childish, which consists of the word child and the bound form -ish.
complex sentence.

Mathematics. pertaining to or using complex numbers: complex methods; complex vector space.

noun

an intricate or complicated association or assemblage of related things, parts, units, etc.: the entire complex of our educational system; an apartment complex.

Psychology. a system of interrelated, emotion-charged ideas, feelings, memories, and impulses that is usually repressed and that gives rise to abnormal or pathological behavior.

a fixed idea; an obsessive notion.

Mathematics.

an arbitrary set of elements of a group.
a collection of simplexes having specified properties.

Also called coordination compound. Chemistry. a compound in which independently existing molecules or ions of a nonmetal (complexing agent ) form coordinate bonds with a metal atom or ion.Compare ligand (def. 2).

Biochemistry. an entity composed of molecules in which the constituents maintain much of their chemical identity: receptor-hormone complex, enzyme-substrate complex.

verb (used with object)

Chemistry. to form a complex with.

verb (used without object)

Chemistry. to form a complex.

OTHER WORDS FOR complex

3 knotty, tangled, labyrinthine.

6 network, web, tangle, labyrinth.

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OPPOSITES FOR complex

2, 3 simple.

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Origin of complex

First recorded in 1645–55; 1905–10 for def. 7; adjective from Latin complexus, past participle of complectī, complectere “to embrace, encompass, include,” equivalent to complect- (see complect) + -tus past participle suffix; noun from Late Latin complexus “totality, complex” (Latin: “inclusion, grasping, embrace”), equivalent to complect(ere) + -tus suffix of verb action; reanalysis of the Latin verb as “to intertwine (completely)” influenced sense of the adjective

OTHER WORDS FROM complex

com·plex·ly, adverbcom·plex·ness, nouno·ver·com·plex, adjectivequa·si-com·plex, adjective

qua·si-com·plex·ly, adverbsu·per·com·plex, adjectiveun·com·plex, adjectiveun·com·plex·ly, adverbun·com·plex·ness, noun

Words nearby complex

complete transduction, completing the square, completion, completionist, completist, complex, complex absence, complex analysis, complex carbohydrate, complex conjugate, complex fraction

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

How to use complex in a sentence

This issue of underutilized existing housing is complex and there’s not much hard data, so it’s a natural fit for us to work on bringing clarity and new ideas to this conversation.
Vacancy Tax Study Is Giving City Officials Déjà Vu|Lisa Halverstadt and Andrew Keatts|February 10, 2021|Voice of San Diego
The most complex global and societal issues can be broken down into smaller solvable tech challenges.
The rise of the activist developer|Walter Thompson|February 9, 2021|TechCrunch
Throughout the game Mono navigates disturbing environments — like drab apartment complexes or a hospital overrun with sentient mannequins — each filled with furniture two sizes too large.
‘Little Nightmares II’ made me dread every moment. And I loved it.|Elise Favis|February 9, 2021|Washington Post
“It’s not just proteins, it’s a complex, emotional product,” says Aleph chief executive Didier Toubia.
Raising the steaks: First 3-D-printed rib-eye is unveiled|Laura Reiley|February 9, 2021|Washington Post

Per the agreement, organizations are limited to 75 players and 75 staff at their complexes, and are encouraged to spread them out as much as possible.
MLB, players’ union agree to health and safety protocols, clearing way for spring training to start|Chelsea Janes|February 9, 2021|Washington Post
It was a complex task they were asked to do, and every cultural and experiential advantage would be required.
Why Did We Panic After 9/11 and Ignore All We Knew About Responding to Security Threats?|Deborah Pearlstein|December 18, 2014|DAILY BEAST
However, their presence shows that Mars could have a more complex and evolving chemical story.
Methane on Mars: Life or Just Gas?|Matthew R. Francis|December 17, 2014|DAILY BEAST
KSM enters the complex through a “Sally Port,” a series of gates designed to allow just one vehicle in at a time.
9/11 Mastermind Is Afraid of the Ladies|Tim Mak|December 16, 2014|DAILY BEAST
We are a huge, complex, diverse country still offering freedom, opportunity and hope.
Dick Cheney vs. ‘Unbroken’|Mike Barnicle|December 15, 2014|DAILY BEAST
If Congress struggles to keep the lights on, how could it deal with issues as complex as police brutality?
Sharpton Recalls Civil Rights Struggle in DC March Against Police Violence|Ben Jacobs|December 13, 2014|DAILY BEAST
The act of the Covenanting Society is complex, and is the aggregate of the actings of all who compose it.
The Ordinance of Covenanting|John Cunningham
He knows when a sentiment is simple and when it is complex, when the heart is a dupe of the mind and when of the senses.
Repertory Of The Comedie Humaine, Complete, A -- Z|Anatole Cerfberr and Jules Franois Christophe
The solution of the problem, if complex in all clinical affections, is especially so in epilepsy.
A Statistical Inquiry Into the Nature and Treatment of Epilepsy|Alexander Hughes Bennett
Bud did not say anything; your efficient chauffeur reserves his eloquence for something more complex than a dead engine.
Cabin Fever|B. M. Bower
It is the most complex of all, as the lines contain internal rimes.
Chaucer's Works, Volume 1 (of 7) -- Romaunt of the Rose; Minor Poems|Geoffrey Chaucer

British Dictionary definitions for complex

complex

/ (ˈkɒmplɛks) /

adjective

made up of various interconnected parts; composite

(of thoughts, writing, etc) intricate or involved

grammar

(of a word) containing at least one bound form
(of a noun phrase) containing both a lexical noun and an embedded clause, as for example the italicized parts of the following sentence: I didn't know the man who served me
(of a sentence) formed by subordination of one clause to another

maths of or involving one or more complex numbers

noun

a whole made up of interconnected or related partsa building complex

psychoanal a group of emotional ideas or impulses that have been banished from the conscious mind but that continue to influence a person's behaviour

informal an obsession or excessive fearhe's got a complex about cats

Also called: coordination compound a chemical compound in which molecules, groups, or ions are attached to a central metal atom, esp a transition metal atom, by coordinate bonds

any chemical compound in which one molecule is linked to another by a coordinate bond

Derived forms of complex

complexly, adverbcomplexness, noun

Word Origin for complex

C17: from Latin complexus, from complectī to entwine, from com- together + plectere to braid

usage for complex

Complex is sometimes wrongly used where complicated is meant. Complex is properly used to say only that something consists of several parts. It should not be used to say that, because something consists of many parts, it is difficult to understand or analyse

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medical definitions for complex

complex

[ kŏm′plĕks′ ]

A group of related, often repressed memories, thoughts, and impulses that compel characteristic or habitual patterns of feelings, thought, and behavior.

The relatively stable combination of two or more ions or compounds into a larger structure without covalent binding.

A composite of chemical or immunological structures.

An entity made up of three or more interrelated components.

A group of individual structures known or believed to be anatomically, embryologically, or physiologically related.

The combination of factors, symptoms, or signs that forms a syndrome.

adj.

Consisting of interconnected or interwoven parts; composite.

Composed of two or more units.

Relating to a group of individual structures known or considered to be anatomically, embryologically, or physiologically related.

complex

OTHER WORDS FOR complex

OPPOSITES FOR complex

Origin of complex

OTHER WORDS FROM complex

Words nearby complex

Words related to complex

How to use complex in a sentence

British Dictionary definitions for complex

Derived forms of complex

Word Origin for complex

usage for complex

Medical definitions for complex