Usage of the phrase, heavily popularised by US President Donald Trump, is said to have increased by 365 per cent since 2016.
Defined as “false, often sensational, information disseminated under the guise of news reporting”, fake news will now be added to the next print edition of the Collins Dictionary.
Dictionary compilers found words and terms associated with politics had enjoyed a surge over the past 12 months.
“Corbynmania” enjoyed a resurgence in 2017 thanks to general election coverage, after first surfacing in 2015.
Helen Newstead, Collins’ head of language content, said: “Much of this year’s list is definitely politically charged, but with a new president in the US and a snap election in the UK it is perhaps no surprise that politics continues to electrify the language.
“Fake news, either as a statement of fact or as an accusation, has been inescapable this year.
“It has contributed to the undermining of society’s trust in news reporting.
“Given the term’s regular usage by President Trump, it is clear that Collins’ Word of the Year, fake news, is very real news.”