Did you know?

Click any word in a definition or example to find the entry for that word

system - definition and synonyms


What are red words?

90% of the time, speakers of English use just 7,500 words in speech and writing. These words appear in red, and are graded with stars. One-star words are frequent, two-star words are more frequent, and three-star words are the most frequent.



The thesaurus of synonyms and related words is fully integrated into the dictionary. Click on the thesaurus category heading under the button in an entry to see the synonyms and related words for that meaning.

noun system pronunciation in American English /ˈsɪstəm/
Word Forms
  • Facebook
  • Twitter
  1. 1
    [countable] a set of connected things that work together for a particular purpose

    a central heating system

    I decided to install a security system to prevent any break-ins.

    1. a.
      a set of organs, tubes, etc. in your body that work together
      cardiovascular/circulatory system:

      First, check that the circulatory system is working properly.

    2. b.
      a set of pieces of equipment or computer programs that work together

      a new computer system

      system requirements (=the type of software, hardware, and the amount of memory needed to operate a program):

      The system requirements for this program are listed below.

  2. 2
    [countable/uncountable] a method of organizing or doing things

    a two-party/multiparty system

    the criminal justice system

    system for:

    They are introducing a very sophisticated system for delivering information.

    system of:

    a democratic system of government

    system to:

    There is simply no system to the way Joshua works.

    1. a.

      the system

      rules that decide how a society, country, or organization should operate and that cannot be changed even though they seem unfair to you

      You can’t beat the system.

  3. 3
    your body considered as a set of connected organs, tubes, etc.

    Lack of sleep can be hard on the system.



to fall over forwards so that your face hits the ground or another surface

BuzzWord Article

Open Dictionary


the activity of exploring abandoned buildings and other manmade structures

add a word


A must for anyone with an interest in the changing face of language. The Macmillan Dictionary blog explores English as it is spoken around the world today.

global English and language change from our blog
Macmillan learn live love play