Why are hidden villages called such? There are several hidden villages, which are supposed to be hidden (it is all in the name..!) But, everyone (at least everyone who matters) seem to know where these hidden villages are. Or, are at least able to easily find out where they are.

So, why are they called hidden villages? Is it more a 'title' or 'status' for these villages?
The literal translation for Konohagakure no Sato is "Village hidden in the leaves" (not hidden leaf village). Here hidden is used in the sense of "surrounded by" or "enclosed by". It does not mean those places are literally hidden from the world. It is similar for other villages, such as Amegakure no Sato (village hidden in the rain), Sunagakure no Sato (village hidden in the sand), etc.