The referring to someone as a patriot, you are typically saying that the person is very passionate about their country and they support it. While that has always been the case, the word has in fact been used to insult someone during the American Revolution.
It's not people thought it was an insult to be loyal to one's country, but rather they were using the word ironically and a little sarcastically in the mid 18th century. In fact, people that were keeping definitions of words in England actually wrote in that the word patriot 'is sometimes used for a factious disturber of the government'!
For more on the word etymology, click the source! To see an example of the perfect American Patriot, take a look at the picture on this article!