'Big' and 'Large'

What's the difference between 'big' and 'large'?

In terms of size, 'big' and 'large' are the same, yet there are differences between these two adjectives.

  1. Formality
    'Big' is used both in writing and in coversation. 'Large' is more formal.

  2. Amounts / Quantities
    You can use 'large' to talk about amounts or quantities but not 'big'.

    e.g. I eat a large amount of fruit every day.
    e.g. A large quantity of drug were found in Yuen Long yesterday.

  3. Age
    You can use 'big' to mean 'older' but not 'large'.

    He's my big brother.

  4. Fixed phrases
    Some phrases are just used together in a certain way. If you change a word, it wouldn't sound correct to other people!

    e.g. a big deal Correct
    e.g. a large deal wrong

    e.g. a big surprise Correct
    e.g. a large surprise wrong

    e.g. a big decision Correct
    e.g. a large decision wrong

    e.g. He has a big mouth. Correct
    e.g. He has a large mouth. wrong