A fascist is a follower of a fascist ideology. Such an ideology is not nessecarily rightwing nor does it have to be a dictatoship. Fascism is marked out by its underlying motive being what griffen called paliengenetic ultranationalism, extreme nationalist feeling focused on a nation reclaiming it's glorious past. Examples include Nazi Germany, Fascist Italy, Stalinist Russia and the current pan-islamic jihad aimed at recreating the Caliphate
"I wish only to reclaim the former glory of our great forebears the Holy Roman Empire"