Question

Question #30443

Answer 1

The 'small' is implied.

Explanation:

'A small' refers to a small 'it' - whatever 'it' was that the person was desiring in a bigger size. There is no need to restate terms, for example 'have you got a ball in a bigger size? This is a small ball', as the fact that you are referring to a ball is self-evident.

Answer 2

Yes, in the example sentence, the word "small" is a noun, a word for a clothing size; a word for a thing.

Explanation:

The article "a" is the clue.
If the sentence was referring to anything other than a size of clothing, the sentence may read, "Have you got it in a bigger size? This is too small."
There are many other variations for a sentence following, "Have you got it in a bigger size?", depending on the thing (it) referred to.