Originally Posted by
ProleOnParole
They're not the same. Lots of lexical differences between Taiwanese Minnan and the varieties spoken elsewhere (such as by the Straits Chinese, i.e. those who primarily call their language "Hokkien" I think). In particular, numerous Japanese loanwords absent from other flavors of Minnan, such as 中古 or 便當 (the latter also happens to be part of your username). For the most part, the languages have been developing independently for centuries. So, shortening "Taiwanese Minnan/Hokkien" to "Taiwanese" is more accurate than calling it just "Minnan" or "Hokkien" in my opinion. And it's also what the language users themselves seem to commonly call it.
Some years ago I was with an electoncis supplies company and I was surprised how different the Taiwanese names for some items were from Mandarin. At first I was afraid we were having major language problems. Circuit breaker "斷路器" in Mandarin bore no resemblance to what it was being called in Taiwanese. Then someone explained many of these "newer" words in Taiwanese came from Japanese, in this case "bure-ka" (sorry no Japanese langauge pack on this pc), which itself was from the English word "breaker"!