When the word 'inflation' is used in an economic discussion, unless specified otherwise, it means price inflation. The word itself does not say anything about the cause. Generally speaking, in the macroeconomic sphere, inflation has a monetary cause.
Friedman said, " inflation is always and everywhere a monetary phenomenon." In a microeconomic sense, which is not the sense that Friedman meant, his quip is categorically wrong. But now we have ample evidence that it can be wrong in the Macro sense as well. Had he not been so given to overstatement he might have said, "inflation is usually a monetary phenomenon" and let it go at that, but his ego would not permit a more more modest phrasing.
http://www.bis.org/publ/bppdf/bispap77e.pdf
Friedman said, " inflation is always and everywhere a monetary phenomenon." In a microeconomic sense, which is not the sense that Friedman meant, his quip is categorically wrong. But now we have ample evidence that it can be wrong in the Macro sense as well. Had he not been so given to overstatement he might have said, "inflation is usually a monetary phenomenon" and let it go at that, but his ego would not permit a more more modest phrasing.
http://www.bis.org/publ/bppdf/bispap77e.pdf