Collins Dictionary has recognised the word "non-binary", whilst also naming "climate strike" as its Word of the Year 2019.

The dictionary said it added the term "non-binary" in recognition of "changes in how people relate to each other and define themselves".

A person who identifies as non-binary does not define themselves exclusively as masculine or feminine and generally prefers they/them pronouns, rather than he/she.

Collins defines non-binary, which can also be spelled nonbinary, as "relating to a gender or sexual identity that does not conform to the binary categories of male or female, heterosexual or homosexual".

Pop star Sam Smith came out as non-binary this year, sparking a debate over gender and sexuality, and was among the first celebrities to ask the public to refer to them using they/them pronouns.

Collins has recognised the term "bopo", short for body positivity, a movement which advocates people being proud of their bodies whatever their shape or size.

"Climate strike" - the word of the year - refers to a snowballing movement sparked by 16-year-old environmental campaigner Greta Thunberg's student protests outside the Swedish parliament.

The term was first registered by Collins' lexicographers in November 2015 when the first event of its kind took place during the United Nations Climate Change Conference in Paris.

It was used on average 100 times more in 2019 than the previous year.

Alongside "climate strike", Collins has also added the term "rewilding", the practice of returning land to a wild state.

A number of recent political terms have also been recognised.

"Double down" describes those who "refuse to give ground" rather than concede a mistake, while "cancelled" is defined as "publicly ceasing to acknowledge a person, organisation, etc, esp on social media, in order to express disapproval of their activities or opinions".

The term "influencer", the TV genre of "hopepunk" and the digital imaging technique of "deepfakes" also feature.

Ten words in Collins 'Brexicon'

Collins Dictionary has also released a list of words that have come into use since the Brexit referendum in 2016.

Brexiteer - noun - a supporter or architect of the withdrawal of Britain from the European Union.

Brexiety - noun - a state of heightened anxiety triggered by concerns about the imminent withdrawal of Britain from the European Union.

Cakeism - noun - a wish to enjoy two desirable but incompatible alternatives.

Flextension - noun - An informal agreement to extend the time allowed for payment of a debt or completion of a contract, setting a new date that can be altered depending on future events.

Milkshake - verb - to throw a milkshake or similar drink over a public figure to humiliate him or her.

No-deal - adjective - denoting a situation in which two parties fail to reach an agreement about how to proceed.

Project Fear - noun - a name given to any political campaign that seeks to arouse public alarm about proposed changes to the status quo.

Prorogue - verb - to discontinue the meetings of (a legislative body) without dissolving it.

Stockpiling - noun - the activity of acquiring and storing large quantities of goods.

Remainer - noun - a person who believes the UK should remain in the European Union.

Also included is the related derogatory term Remoaner - noun - a person who continues to argue that the UK should stay in the EU despite the result of the referendum of 2016.

All of the words of the year will be considered for future print editions of the Collins Dictionary.