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a - definition and synonyms


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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.



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determiner stronga pronunciation in British English // weaka pronunciation in British English /ə/
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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

    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 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 as ‘a lot’, ‘a few’, or ‘a great deal

    a lot of money

    a bit of luck

    Synonyms and related words
  7. 7
    used in numbers and measurements to mean ‘one’, as in ‘a thousand’ or ‘an hour

    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 person’s 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.
      used before the name of a famous artist to mean a picture by that artist

      The gallery has recently acquired a Picasso.

    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


used to describe something which is done more carefully and over a longer period of time …

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Open Dictionary


the practice of giving birth in the presence of several friends and relatives

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