Definition of 'complex'
Word forms: plural complexes
pronunciation note: The adjective is pronounced (kəmpleks
) in American English.
1. adjective
Something that is complex has many different parts, and is therefore often difficult to understand.
2. adjective [ADJECTIVE noun]
In grammar, a complex sentence contains one or more subordinate clauses as well as a main clause. Compare compound, simple.
3. countable noun
A complex is a group of buildings designed for a particular purpose, or one large building
divided into several smaller areas.
4. countable noun [with supplement]
A complex of things is a group or system of things that are connected with each other in a complicated way.
5. countable noun
If someone has a complex about something, they have a mental or emotional problem relating to it, often because
of an unpleasant experience in the past.
6. See also guilt complex, inferiority complex
Collins COBUILD Advanced Learner’s Dictionary. Copyright © HarperCollins Publishers
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British English pronunciation
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Word Frequency
complex in British English
adjective
1.
made up of various interconnected parts; composite
2.
(of thoughts, writing, etc) intricate or involved
3. grammar
a.
(of a word) containing at least one bound form
b.
(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
c.
(of a sentence) formed by subordination of one clause to another
4. mathematics
of or involving one or more complex numbers
noun
▶ 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 analyse5.
a whole made up of interconnected or related parts
a building complex
6. psychoanalysis
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
Collins English Dictionary. Copyright © HarperCollins Publishers
Derived forms
complexly (ˈcomplexly) adverb
complexness (ˈcomplexness)
noun
Word origin
C17: from Latin complexus, from complectī to entwine, from com- together + plectere to braid
Word Frequency
complex in American English
adjective
1.
consisting of two or more related parts
2.
not simple; involved or complicated
noun
SYNONYMY NOTE: complex refers to that which is made up of many elaborately interrelated or interconnected
parts, so that much study or knowledge is needed to understand or operate it [a complex mechanism]; complicated is applied to that which is highly complex and hence very difficult to analyze, solve,
or understand [a complicated problem]; intricate specifically suggests a perplexingly elaborate interweaving of parts that is difficult
to follow [an intricate maze]; involved, in this connection, is applied to situations, ideas, etc. whose parts are thought
of as intertwining in complicated, often disordered, fashion [an involved argument]3.
a group of interrelated ideas, activities, etc. that form, or are viewed as forming, a single whole
4.
an assemblage of units, as buildings or roadways, that together form a single, comprehensive group
5. Psychoanalysis
a.
an integration of impulses, ideas, and emotions related to a particular object, activity, etc., largely unconscious, but strongly influencing the individual's attitudes and behavior
OPPOSITE: simple
Webster’s New World College Dictionary, 4th Edition. Copyright © 2010 by
Houghton Mifflin Harcourt. All rights reserved.
Derived forms
complexly (comˈplexly)
adverb
Word origin
< L complexus, pp. of complecti, to encircle, embrace < com-, with + plectere, to weave: see flaxWord Frequency
complex in American English
( adjective & verb kəmˈpleks, ˈkɑmpleks, noun ˈkɑmpleks)
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
a. (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
b. See complex sentence
5. Math
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
9. Math
a.
an arbitrary set of elements of a group
b.
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 (sense 2)11. Biochemistry
receptor-hormone complex
enzyme-substrate complex
transitive verb
12. Chemistry
to form a complex with
intransitive verb
SYNONYMS 3. knotty, tangled, labyrinthine. 6. network, web, tangle, labyrinth.ANTONYMS 2, 3. simple.13. Chemistry
to form a complex
Most material © 2005, 1997, 1991 by Penguin Random House LLC. Modified entries © 2019
by Penguin Random House LLC and HarperCollins Publishers Ltd
Derived forms
complexly adverb
complexness
noun
Word origin
[1645–55; 1905–10 for def. 7; (adj.) ‹ L complexus, ptp. of complectī, complectere to embrace, encompass, include, equiv. to complect- ( see complect) + -tus ptp. suffix; (n.) ‹ LL complexus totality, complex (L: inclusion, grasping, embrace), equiv. to complect(ere) + -tus suffix of v. action; reanalysis of the L v. as “to intertwine (completely)” has influenced
sense of the adj.]Word Frequency
complex in Chemical Engineering
(kɒmplɛks)
Word forms: (plural) complexes
noun
(Chemical Engineering: General)
complexingA complex is a substance that is made when two or more simpler compounds join chemically.
Chloramines are chemical complexes formed from the reaction between ammonia and chlorine.
Ferric iron tends to form complexes with natural water organics.
A complex is a substance that is made when two or more simpler compounds join chemically.
Collins COBUILD Key Words for Chemical Engineering. Copyright © HarperCollins Publishers
Examples of 'complex' in a sentence
complex
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In other languages
complex
British English: complex
/ˈkɒmplɛks/ ADJECTIVE
Complex things have many different parts and are hard to understand.
...a complex system of voting.
- American English: complex /kəmˈplɛks/
- Arabic: مُرَكَّب
- Brazilian Portuguese: complexo
- Chinese: 复杂的
- Croatian: složen
- Czech: složitý
- Danish: kompleks
- Dutch: complex
- European Spanish: complejo
- Finnish: monimutkainen
- French: complexe
- German: komplex
- Greek: σύνθετος
- Italian: complesso
- Japanese: 複合の
- Korean: 복잡한
- Norwegian: sammensatt
- Polish: złożony
- European Portuguese: complexo
- Romanian: complex
- Russian: комплексный
- Latin American Spanish: complejo
- Swedish: komplicerad
- Thai: ซับซ้อน
- Turkish: karmaşık
- Ukrainian: складний
- Vietnamese: phức tạp
British English: complex
/ˈkɒmplɛks/ NOUN
A complex is a group of buildings used for a particular purpose.
...a new shopping complex.
- American English: complex /ˈkɑmplɛks/
- Arabic: مُرَكَّب
- Brazilian Portuguese: complexo
- Chinese: 联合体
- Croatian: kompleks
- Czech: komplex
- Danish: kompleks
- Dutch: complex
- European Spanish: complejo
- Finnish: -keskus (can only be used together with a qualifier, e.g. urheilukeskus -sports complex)
- French: complexe
- German: Komplex
- Greek: σύμπλεγμα
- Italian: complesso
- Japanese: 複合体
- Korean: 복합체
- Norwegian: kompleks
- Polish: kompleks
- European Portuguese: complexo
- Romanian: complex
- Russian: комплекс
- Latin American Spanish: complejo
- Swedish: komplex
- Thai: คอมเพล็กซ์ (กลุ่มอาคาร)
- Turkish: kompleks
- Ukrainian: комплекс
- Vietnamese: tòa phức hợp
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Definition of complex from the Collins English Dictionary
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