definition by wikipedia
Fiat money is currency which derives its value from government regulation or law.
My problem is with the semantics, and just because the great oracle of wikipedia qualifies the definition of fiat with the descriptor "government", doesn't mean bitcoin is not a fiat currency as opposed to a commodity currency. My point is that bitcoin is a rather novel way of creating a fiat currency without a government, or at least what is considered a government.
how is it related to bitcoin?
The issue is why people consider Bitcoin not to be a fiat currency.