complex

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

SEE MORE SYNONYMS FOR complex 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.

Origin of complex

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

Related formscom·plex·ly, adverbcom·plex·ness, nouno·ver·com·plex, adjectivequa·si-com·plex, adjectivequa·si-com·plex·ly, adverbsu·per·com·plex, adjectiveun·com·plex, adjectiveun·com·plex·ly, adverbun·com·plex·ness, noun

Synonyms for complex

SEE MORE SYNONYMS FOR complex ON THESAURUS.COM

3. knotty, tangled, labyrinthine. 6. network, web, tangle, labyrinth.

Antonyms for complex

2, 3. simple.

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Related Words for complex

complicated, convoluted, perplexing, sophisticated, intricate, disturbing, obscure, network, system, structure, compound, manifold, composite, conglomerate, motley, multiple, mosaic, multiplex, winding, byzantine

Examples from the Web for complex

Contemporary Examples of complex

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
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
We are a huge, complex, diverse country still offering freedom, opportunity and hope.
Dick Cheney vs. ‘Unbroken’
Mike Barnicle
December 15, 2014
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
Medication can now be taken in a single pill rather than a complex cocktail of tablets.
The New Face of HIV Is Gay & Young
Adebisi Alimi
December 1, 2014

Historical Examples of complex

The case of Yates was by all odds the most complex and bewildering of the four.
In the Midst of Alarms
Robert Barr
It is only the artificial and the complex that bewilder them.
The Gorgon's Head
Nathaniel Hawthorne
Yours must be the spirit of the times, strenuous, complex, democratic.
The Call of the Twentieth Century
David Starr Jordan
Through them from the garden and the fields entered a complex of sweet odors.
Casanova's Homecoming
Arthur Schnitzler
But the facts are far too complex to enable us thus to rush hastily to an answer.
The Truth About Woman
C. Gasquoine Hartley

British Dictionary definitions for complex

complex

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 Formscomplexly, adverbcomplexness, noun

Word Origin for complex

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

usage

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

Word Origin and History for complex

adj.

1650s, "composed of parts," from French complexe "complicated, complex, intricate" (17c.), from Latin complexus "surrounding, encompassing," past participle of complecti "to encircle, embrace," in transferred use, "to hold fast, master, comprehend," from com- "with" (see com-) + plectere "to weave, braid, twine, entwine," from PIE *plek-to-, from root *plek- "to plait" (see ply (v.1)). The meaning "not easily analyzed" is first recorded 1715. Complex sentence is attested from 1881.

1650s, "a whole comprised of parts," from complex (adj.). Psychological sense of "connected group of repressed ideas" was established by C.G. Jung, 1907.

complex in Medicine

complex

[kŏm′plĕks′]

n.

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.