Visitors to twictionary.collinsdictionary.com have until May 28 to choose from a shortlist of words, with the most popular being added to the dictionary.
The list is a combination of popular hashtags and words that have made the news over the last year and will be the first time a new word has been added via a Twitter vote.
Lucy Mangan (@LucyMangan), a contributor to the Collins English Dictionary and self-confessed word geek, said: "Twitter is the perfect place to find out what people are really saying and how they're saying it. It's a space in which you're freer than almost anywhere else to combine old words, resurrect others or invent totally new ones whenever the need arises. #brilliant."
Andrew Freeman, associate publisher at Collins, said: "Twitter offers us an immediate snapshot of how much a word is used. The tried and tested approach to compiling dictionaries has to adapt to embrace the ways in which language is developing through use on social media, and this is a fun way to get Twitter users involved in defining the English language."
Collins has been publishing the dictionary since 1819 and is the largest single volume dictionary in print, with the words it contains sourced from the Collins Corpus, which contains more than 4.5 billion words, as well as the open source site collinsdictionary.com, where users can submit words for consideration.
Lucy Mangan, a blogger for collinsdictionary.com and a contributor to the Collins English Dictionary, said: "Twitter is the perfect place to find out what people are really saying and how they're saying it. It's a space in which you're freer than almost anywhere else to combine old words, resurrect others or invent totally new ones whenever the need arises. #brilliant."
Ian Brookes, lexicographer and consultant editor to the Collins English Dictionary, said: "Language has always had to develop in response to changes in society and technology. In the 20th century the development of the motor car, air travel, television, and the personal computer changed the things that people did and so brought many new words into the language. In the 21st century, the growth of social media has had a comparable effect.
Here are the candidates along with the official definition they have been given.
:: Adorkable - dorky in an adorable way.
:: Duckface - the traditional pouting facial expression in selfies.
:: Euromaiden - the original pro-Europe protests in Ukraine, named for Maidan Square in Kiev.
:: Fatberg - a large mass of solid waste, grease etc, clogging a sewage system.
:: Felfie - a farmer selfie.
:: Fracktivist - an activist who protests against fracking.
:: Gaybourhood - a gay-friendly neighbourhood, e.g. Castro in San Francisco.
:: Nomakeupselfie - a selfie of a woman without make-up, posted online to raise awareness for a charity.
:: Vaguebooking - posting a deliberately vague status updates on social media to prompt a response.