You don't often see the word 'euergetism' in a tabloid newspaper, but it appears in today's Mail on Sunday. It was used by Boris Johnson, the mayor of London, when he called for wealthy people to fund civic projects and public services. It means the same as philanthropy and derives from the Greek verb 'to do good things'.
Boris Johnson studied Classics as a student, and is clearly very knowledgeable about classical history and literature. However, much as 'euergetism' sounds an ancient Greek word, it isn't. There is no entry for the word in the OED, and I can come up with no 'hits' in a search of a couple of databases - the Times digital archive, which goes back to the 18th century, and another database which covers 19th-century newspapers (by the way, I can use these databases with my local authority library card, and if you live in the UK, so, probably, can you -- just go to the 'Online Reference' section of your local library's website). Google Labs Ngram site of digitalised books has no record of the word before the 1960s. Wikipedia says that the word 'euergetism' was coined in the 1920s by the French historian A Boulanger. Unfortunately, there is no hyperlink for Boulanger, and Wikipedia gives no other information about this person. Googling the name isn't very helpful, as Boulanger is such a common French name, however, it is perhaps the historian André Boulanger who is meant. He was writing in the 1920s and his key work seems to be Aelius Aristide et la sophistique dans la province d'Asie au IIe siècle de notre ère, which ties in with the classical references.