Many pundits used the term jingoism to describe extreme nationalism, usually in a far-right context. This, like its fellow conjugations jingoist, jingoish, and jingoistic, stems from the root jingo, a less commonly used word nowadays, but one that meant "a patriot hawkish on foreign affairs". This usage came from a British nationalistic song where they say "by Jingo!" in describing their military. Before that, by Jingo was an expression that basically stood in as a euphemism for Jesus. While Jingo may just be a corruption of the name of the Christian Messiah, an interesting alternative etymology has also been proposed. Though evidence is scarce, some think that jingo came from the Basque word jinkoa, which meant "god". This would be fascinating, because (of course), Basque is not an Indo-European language and comes from its own family, Proto-Basque. It's probably from Jesus, though (like how gosh is a euphemism for god). Meh.
Adam Aleksic, an incoming freshman at Harvard University, has been described as the internet's sixth most famous etymologist. He has disturbing interests in linguistics, vexillology, geography, board games, limericks, and law, and he loves writing about himself in the third person.
The Etymology Nerd