Late 17th century (originally a conjuror's word): by jingo (and the noun sense) come from a popular song adopted by those supporting the sending of a British fleet into Turkish waters to resist Russia in 1878. The chorus ran: ‘We don't want to fight, yet by Jingo! if we do, We've got the ships, we've got the men, and got the money too’.

• Originally a word said by conjurors when performing a magic trick, rather like abracadabra, jingo became used more widely in the expression ‘by jingo!’ to show how much in earnest a person was. In 1878 the British Prime Minister Benjamin Disraeli (1804–81) was determined to send a fleet into Turkish waters to resist Russia. Popular support for his policy included a music-hall song with the chorus: ‘We don't want to fight, yet by Jingo! If we do, We've got the ships, we've got the men, and got the money too.’ Jingoism as a word for an aggressive patriotism associated with vociferous support for a policy favouring war appeared in the language in the same year.