The Meaning of Complex: What It Is and How To Use It

How can the word complex be used in different ways? This article will detail several meanings of complex and their uses.

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There are several meanings of the word complex; one could say the word complex itself is very complex! Take a look at this article to learn several meanings of the word complex, its origin, example sentences, and more!

What Does the Word Complex Mean?

According to Collins English Dictionary, the word complex has many meanings. The most common meaning of complex is as an adjective meaning complicated or intricate, or having an involved arrangement of parts. A complex can also refer to a collection of buildings or a group of buildings, such as an apartment complex. 

In biochemistry, a complex refers to a structure consisting of a central atom and a composition of molecules that can form coordinate bonds like a receptor-hormone complex. 

In psychology, a complex is a type of pathological or strange behavior or emotion resulting from memories, feelings, and impulses. The pronunciation of complex is ˈkɒmplɛks.

What Is the Origin of the Word Complex?

According to Dictionary, the word complex has been used since the 17th century in Middle English. This word comes from the Latin complexus, which is the past participle of complecti, and the Latin complectere, which means to embrace or include. 

How Can Complex Be Used in a Sentence?

Below are example sentences containing the word complex. Studying sentences that contain words you are trying to learn is one of many tactics for memorizing definitions. See if you can determine which definition of complex is used in each of these sentences:

Based on her psychoanalysis, he had all of the symptoms of a superiority complex. The combination of emotions he presented was identical to a person’s behavior who’s been diagnosed with the syndrome.

Jim studied the complex entity of ions in chemistry class and broke it down into its constituents to identify its chemical identity. He broke the whole structure known as a coordination compound into its related structures and related parts from the conceptual whole.

The complex machinery known as an escalator was installed in the shopping malls in town. The use of these complex ideas was new to the people, and a combination of factors led to customers preferring the stairs instead.

The group of emotional ideas led to the woman boss’ pathological behavior and inferiority complex outside of her complex mind. Her obsessive notion and fear of a particular thing necessitated therapy.

He knew how to play a simple folk melody, but he was lost when presented with a complex set of variations. 

She twisted a braid into her hair before attempting the complex process for her mathematics class. One person’s behavior in class insinuated that she would be unsuccessful, but she was able to solve the problem even with its complicated association of the square root of real numbers.

What Are Translations of Complex?

If you need to describe something as being complex to a person who does not speak English, reference these translations of complex that are provided by Nice Translator.

  • Marathi: कॉम्प्लेक्स
  • Turkish: karmaşık
  • Romanian: complex
  • Finnish: monimutkainen
  • Lithuanian: Kompleksas 
  • Chinese (Taiwan): 複雜的
  • Portuguese (Portugal): complexo
  • Danish: kompleks.
  • Polish: złożony
  • Tamil: சிக்கலான
  • Ukrainian: комплексний
  • Urdu: کمپلیکس
  • Bulgarian: комплекс
  • Malay: kompleks
  • Thai: ซับซ้อน
  • Chinese (PRC): 复杂的
  • Greek: συγκρότημα
  • Italian: complesso
  • Basque: konplexu
  • Slovenian: kompleks
  • Portuguese (Brazil): complexo
  • Swedish: komplex
  • French: complexe
  • Norwegian: kompleks
  • Amharic: ውስብስብ
  • Hungarian: összetett
  • Russian: сложный
  • Catalan: complex
  • Vietnamese: phức tạp
  • Indonesian: kompleks
  • Hebrew: מורכב
  • Latvian: komplekss
  • Croatian: kompleks
  • Gujarati: સંકુલ
  • Icelandic: flókið
  • Welsh: gymhleth
  • Czech: komplex
  • Telugu: క్లిష్టమైన
  • Filipino: mahirap unawain
  • Malayalam: കോംപ്ലമായ
  • German: Komplex
  • Serbian: комплекс
  • Bengali: জটিল
  • Estonian: kompleksne
  • Korean: 복잡한
  • Spanish: complejo
  • Japanese: 繁雑
  • Slovak: komplexný
  • Dutch: complex
  • Swahili: tata
  • Arabic: مركب
  • Hindi: जटिल
  • Kannada: ಸಂಕೀರ್ಣ

What Are Synonyms of the Word Complex?

Power Thesaurus lists many words that can be used in place of the word complex. These words are called synonyms, and have similar definitions to the word complex.

  • abstruse
  • anfractuous
  • arduous
  • awkward
  • baffling
  • bewildering
  • burdensome
  • byzantine
  • challenging
  • complexity
  • complicated
  • composite
  • compound
  • confusing
  • convoluted
  • cumbersome
  • daedal
  • deep
  • difficult
  • disturbing
  • elaborate
  • esoteric
  • fixation
  • gordian
  • grinding
  • hang-up
  • hard
  • hard to understand
  • heterogeneous
  • impenetrable
  • incomprehensible
  • inextricable
  • intricate
  • involute
  • involved
  • knotted
  • knotty
  • laborious
  • labyrinthine
  • multiple
  • multiplex
  • nasty
  • network
  • neurosis
  • obscure
  • obsession
  • operose
  • oppressive
  • painful
  • perplexed
  • perplexing
  • precarious
  • problematic
  • profound
  • puzzling
  • recondite
  • rough
  • rugged
  • sensitive
  • severe
  • sinuous
  • sophisticated
  • sticky
  • stressful
  • structure
  • system
  • tangled
  • tangly
  • thorny
  • ticklish
  • tight
  • toilsome
  • tortuous
  • tough
  • tricky
  • trying
  • unfathomable
  • weighty

What Are Antonyms of the Word Complex?

Complex also has several antonyms which are listed below from Power Thesaurus. These words are opposites of the word complex.

  • ancient
  • antediluvian
  • antiquated
  • antique
  • apparent
  • archaic
  • as easy as ABC
  • as easy as falling off a log
  • as easy as pie
  • as easy as rolling off a log
  • as easy as shooting fish in a barrel
  • as simple as ABC
  • austere
  • backward
  • bald
  • bare
  • basic
  • can be done with your eyes closed
  • can be done with your eyes shut
  • childlike
  • clear
  • crystal clear
  • dated
  • direct
  • dull
  • early
  • easily understood
  • easy
  • easy as pie
  • easy as shelling peas
  • easy as shooting fish in a barrel
  • easy peasy Japanesey
  • easy to achieve
  • effortless
  • elementary
  • evident
  • fairly straightforward
  • hassle-free
  • homogeneous
  • isolation
  • like shooting fish in a barrel
  • low
  • modest
  • natural
  • nonprogressive
  • obsolete
  • obvious
  • old
  • old-fashioned
  • ordinary
  • outdated
  • outmoded
  • plain
  • plain sailing
  • poor
  • primitive
  • royal
  • rudimentary
  • simple
  • simplistic
  • spartan
  • stark
  • straightforward
  • unadorned
  • uncomplicated
  • uniform
  • unsophisticated


The word complex has several meanings. The most common meaning of the word complex is intricate or complicated. The word complex is very versatile and can be used in many ways.


  1. Complex synonyms – 1 582 Words and Phrases for Complex | Power Thesaurus 
  2. Complex antonyms – 538 Opposites of Complex | Power Thesaurus 
  3. Complex Definition & Meaning | 
  4. Complex definition and meaning | Collins English Dictionary
  5. Complex | Nice Translator