Dear R:

You wrote:
> Can you provide guidance as to which term is correct: Biggest vs. Largest. Are there circumstances / rules that dictate which word should be used? Or are both correct in any circumstance.
>
> Thank you for your assistance.
>
The two words are very similar in meaning and use. In many cases they can be used interchangeably. However, there is a tendency for “big” to refer to size and “large” to refer to quantity. There is certainly an overlap, but you are more likely to hear that a million is a big number and a million pounds (or dollars) is a large amount of money.