it means great amount
Notably large in size or extent.
It could mean a large roll of hair on the back or top of the head, or it could mean a large buttocks or it could just mean a large bread roll.
This is not an idiom. If you see "as ___ as ____" you are dealing with a simile or comparison between two things. Remember AS = A Simile. This is just saying something is very large, as a buffalo is a large animal.
It means according to one explanation or view, or to a certain extent.
It's not really an idiom. It means "what are you thinking about."
RFP is not an idiom. It's an abbreviation.
It is not an idiom, it means your nose is itching.
The idiom "slept like a log" means sleeping very deeply and soundly, to the extent that one is completely unaware of their surroundings and doesn't wake up easily. The phrase is often used to describe a very restful and uninterrupted sleep.
idiom means expression like a page in a book
It's not an idiom. It means the tip of your nostril.
"Sieve" is not an idiom. See the related link.
This is not an idiom. It is a measurement. $100,000 is how you write it in numbers.