Patriotism means loyalty of person to his/her own nation or the leaders of nation. A patriot is a person who is on the side of his/her own nation or its leaders. Patriotism is different from nationalism. Nationalist thinks that every ethnic group should have its own nation, so nations are to serve the people. In other words in nationalism the nation is just a tool to have freedom for an ethnic group, while in patriotism the nation itself is the highest value.
The English term "patriot" is first known from the Elizabethan era, via Middle French from Late Latin (6th century) patriota "countryman", ultimately from Greek πατριώτης (patriōtēs) "countryman", from πατρίς (patris), "fatherland". The abstract noun patriotism appears in the early 18th century..