Did you know?

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

a - 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.

determiner stronga pronunciation in British English // weaka pronunciation in British English /ə/
  • Facebook
  • Twitter

or an stronga pronunciation in British English /æn/ weaka pronunciation in British English /ən/

A or an is used as an indefinite article, usually followed by a singular countable noun.
A is used when the next word begins with a consonant.
An is used when the next word begins with a vowel sound.
When a word begins with the letter ‘u’ that is pronounced /juː/, the word is treated as starting with a consonant: a university.
When a word begins with a silent ‘h’, it is treated as starting with a vowel: an hour.
The names of the letters f, h, l, m, n, r, s, and x begin with vowel sounds, so abbreviations that begin with one of these letters are treated as starting with a vowel: an MPan HGV.
  1. 1
    used when you are mentioning a person or a thing for the first time, or when the person listening to you does not already know about them
    I have an idea.
    There’s a concert on Sunday night.
    Synonyms and related words
  2. 2
    used when you mean any person or thing of a particular type, but you are not referring to a specific one
    You need a dictionary.
    I haven’t got an umbrella.
    Children must be accompanied by an adult.
    Synonyms and related words
  3. 3
    used when you say what class, type, or group someone or something belongs to, or what job someone has
    He’s a liar and a cheat.
    Greece has been a republic since 1973.
    Ruth’s father was a lawyer.
    Synonyms and related words
  4. 4
    used before a singular noun that represents every person or thing of a particular type
    A dog needs regular exercise.
    A molecule consists of two or more atoms.
    Synonyms and related words
  5. 5
    used when you are referring to a person or thing as one of several people or things of this type
    I want you to meet a friend of mine.
    He’s a member of the team.
    Synonyms and related words
  6. 6
    used in expressions of quantity such asa lot’, ‘a few’, ora great deal
    a lot of money
    a bit of luck
    We all appreciate a little encouragement.
    Synonyms and related words
  7. 7
    used in numbers and measurements to meanone’, as ina thousandoran hour
    a million dollars
    a hundred years ago
    a minute or two
    Synonyms and related words
  8. 8
    used in phrases showing how much something costs, how often it happens, how fast it goes etc
    Meetings are held four times a year.
    Tomatoes are £1.20 a kilo (=each kilo costs £1.20).
    The car was travelling at 90 miles an hour.
    Synonyms and related words
  9. 9
    used before a noun that means a substance, product, food etc when referring to a particular type of it
    Brie is a soft creamy cheese.
    Plants won’t grow in a soil that contains too much lime.
    Synonyms and related words
  10. 10
    used before the name of some drinks to mean a cup or glass of that drink
    I’ll just have a beer, thanks.
    Have you got time for a coffee?
    Synonyms and related words
  11. 11
    used before a noun that means a particular quality or feeling when the quality or feeling is described in some way
    Sales staff must have a good working knowledge of French.
    They fought back with a fierce determination that surprised the invaders.
    Synonyms and related words
  12. 12
    used before a noun that is formed from a verb and means a single action of that verb
    Can I have a try?
    Let’s take a walk round the garden.
    Synonyms and related words
  13. 13
    used before a noun that expresses your feelings about a situation
    It’s a relief to know they’re safe.
    What a shame he couldn’t be there to receive the prize!
    Synonyms and related words
  14. 14
    used before the name of a particular day, season, or holiday to mean one particular Tuesday, summer, Christmas etc
    It was a bitterly cold winter.
    She was born at six o’clock on a Sunday morning.
    Synonyms and related words
  15. 15
    used before a persons name when you do not know anything about them
    There’s a Mr Alex Murray asking to see you.
    Synonyms and related words
    1. a.
    2. b.
      used before a family name to mean a member of that family
      Remember you’re an Osborne – it’s a name to be proud of.
      Synonyms and related words
    3. c.
      used before the name of a famous person to mean someone else with similar abilities, a similar appearance, or a similar character
      Already he is being hailed as a young Albert Einstein.
      Synonyms and related words


an area in the countryside where there are both housing developments and farms, and many people travel to work in nearby cities

BuzzWord Article

Open Dictionary

troll factory

a company that pays its employees to write online comments in favour or against somebody or something posing as ordinary Internet users

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