"Kind of" means not exactly, but close. If you ask "is the sky blue" when it is cloudy, someone might say "kind of." You could also use this as an adjective, as in "that dress is kind of green and kind of brown. Another term that means the same is "sort of."
It emphasizes uniqueness.
Nothing - it looks like some kind of abbreviation instead of an idiom.
It's an idiom.
It's kind of like "blew his top", which means that he/someone had an outburst of anger.
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.
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.
i think its an idiom, but i think the saying is "You lucky duck"
This is not an idiom. It is a measurement. $100,000 is how you write it in numbers.