complex

[adj., v. kuh m-pleks, kom-pleks; n. kom-pleks] /adj., v. kəmˈplɛks, ˈkɒm plɛks; n. ˈkɒm plɛks/
adjective
1.
composed of many interconnected parts; compound; composite:
a complex highway system.
2.
characterized by a very complicated or involved arrangement of parts, units, etc.:
complex machinery.
3.
so complicated or intricate as to be hard to understand or deal with:
a complex problem.
4.
Grammar.
  1. (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.
  2. complex sentence.
5.
Mathematics. pertaining to or using complex numbers:
complex methods; complex vector space.
noun
6.
an intricate or complicated association or assemblage of related things, parts, units, etc.:
the entire complex of our educational system; an apartment complex.
7.
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.
8.
a fixed idea; an obsessive notion.
9.
Mathematics.
  1. an arbitrary set of elements of a group.
  2. a collection of simplexes having specified properties.
10.
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).
11.
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)
12.
Chemistry. to form a complex with.
verb (used without object)
13.
Chemistry. to form a complex.
Origin
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 forms
complexly, adverb
complexness, noun
overcomplex, adjective
quasi-complex, adjective
quasi-complexly, adverb
supercomplex, adjective
uncomplex, adjective
uncomplexly, adverb
uncomplexness, noun
Synonyms
3. knotty, tangled, labyrinthine. 6. network, web, tangle, labyrinth.
Antonyms
2, 3. simple.
Examples from the web for complex
  • To understand those more complex historical issues, students must know the approximate dates of the famine.
  • Pinpointing the genes involved in cancer will help chart a new course across the complex landscape of human malignancies.
  • The policy process essentially maps a problem, no matter how complex, on binary possibilities.
  • Yet the current crime problem is being debated in far richer and more complex terms locally.
  • And since each flat tile is relatively simple and easy to make, it becomes much cheaper and easier to build complex cloaks.
  • Basil has a bright, complex, and slightly anise flavor that enhances a wide array of summer fruits and vegetables.
  • Commercial manufacturers can make it quickly, so they do-which means that rich, complex flavors never develop.
  • Maybe you decided to keep that amorous rooster or maybe you have a raging chicken-rescuing complex.
  • The complex also includes two gas stations, two camp stores, a picnic area and a ranger station with a first aid facility.
  • The simple-sounding grunts and hoots of the toadfish contain surprisingly complex information.
British Dictionary definitions for complex

complex

/ˈkɒmplɛks/
adjective
1.
made up of various interconnected parts; composite
2.
(of thoughts, writing, etc) intricate or involved
3.
(grammar)
  1. (of a word) containing at least one bound form
  2. (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
  3. (of a sentence) formed by subordination of one clause to another
4.
(maths) of or involving one or more complex numbers
noun
5.
a whole made up of interconnected or related parts: a building complex
6.
(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
7.
(informal) an obsession or excessive fear: he's got a complex about cats
8.
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
9.
any chemical compound in which one molecule is linked to another by a coordinate bond
Derived Forms
complexly, adverb
complexness, noun
Usage note
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
Word Origin
C17: from Latin complexus, from complectī to entwine, from com- together + plectere to braid
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.

n.

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 com·plex (kŏm'plěks')
n.

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

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

  3. A composite of chemical or immunological structures.

  4. An entity made up of three or more interrelated components.

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

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

adj. (kəm-plěks', kŏm'plěks')

  1. Consisting of interconnected or interwoven parts; composite.

  2. Composed of two or more units.

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

Encyclopedia Article for complex

in chemistry, a substance, either an ion or an electrically neutral molecule, formed by the union of simpler substances (as compounds or ions) and held together by forces that are chemical (i.e., dependent on specific properties of particular atomic structures) rather than physical. The formation of complexes has a strong effect on the behaviour of solutions. See also chemical association; coordination compound.

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