I don't think most supporters of Scottish independence fit the dictionary definition of nationalism at all:I don’t especially like being called a nationalist simply because I want independence, but there’s a certain group of folk who don’t want independence that really really hate being called unionists. Oddly those same folk are totally fine calling me a nationalist or a Nat if they’re feeling rather perky.
"a person who strongly identifies with their own nation and vigorously supports its interests, especially to the exclusion or detriment of the interests of other nations"
To me that's a clearer description of the UK government than the Scottish government. The outcome of the EU referendum also indicates that England is more nationalist than Scotland in my view.
Nationalist as a term does tend to be used by the likes of Boris Johnson and certain posters in ad hominem attacks. It plays well in support of their positions I suppose.