1

complex

noun com·plex \ ˈkäm-ˌpleks \
Updated on: 19 Nov 2017

Definition of complex

1 :a whole made up of complicated or interrelated parts
  • a complex of welfare programs
  • the military-industrial complex
2 a :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

Examples of complex in a Sentence

  1. She has a complex about her appearance.

  2. a complex of protein molecules

Recent Examples of complex from the Web

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.

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”).

Origin and Etymology of complex

Late Latin complexus totality, from Latin, embrace, from complecti — see 2complex

Other Chemical Engineering Terms


2

complex

adjective com·plex \ käm-ˈpleks , kəm-ˈpleks , ˈkäm-ˌpleks \

Definition of complex

1 a :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

complexly

adverb

complexness

noun

Examples of complex in a Sentence

  1. The house's wiring is complex.

  2. The situation is more complex than you realize.

Recent Examples of complex from the Web

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.

Origin and Etymology of complex

Latin complexus, past participle of complecti to embrace, comprise (a multitude of objects), from com- + plectere to braid — more at ply

Synonym Discussion of complex

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

3

complex

verb com·plex \ käm-ˈpleks , kəm-ˈpleks , ˈkäm-ˌpleks \

Definition of complex

transitive verb
1 :to make complex or into a complex
2 :chelate

complexation

play \ˌkäm-ˌplek-ˈsā-shən, kəm-\ noun

Examples of complex in a Sentence

  1. there's no need to complex what should be a simple process for obtaining a building permit

Recent Examples of complex from the Web

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.

First Known Use of complex

1658

Other Chemical Engineering Terms


COMPLEX Defined for English Language Learners

complex

noun

Definition of complex for English Language Learners

  • : 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

Definition of complex for English Language Learners

  • : 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 Defined for Kids

complex

adjective com·plex \ käm-ˈpleks , kəm-ˈpleks , ˈkäm-ˌpleks \

Definition of complex for Students

1 :not easy to understand or explain :not simple
  • complex instructions
2 :having parts that go together in complicated ways
  • a complex invention

Medical Dictionary

1

complex

adjective com·plex \ käm-ˈpleks , kəm-ˈ , ˈkäm-ˌ \

medical Definition of complex

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

2

complex

noun com·plex \ ˈkäm-ˌpleks \

medical Definition of complex

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

3

complex

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

medical Definition of complex

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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