It's the trans-Tasman combination that led to the toppling of nine parliamentarians and question marks over many more.
And now the Australian National Dictionary Centre has declared "Kwaussie" - a person who is a dual citizen of Australia and New Zealand, a New Zealander living in Australia or a person of Australian and New Zealand descent - the word of the year.
Centre director Amanda Laugesen said staff had chosen Kwaussie for the influence the citizenship crisis had on Australia's political, cultural and social landscape in 2017.
Former Greens senator Scott Ludlam was the first politician to fall foul of the constitution after realising he was a citizen of both Australia and New Zealand. Fellow Green Larissa Waters was next, followed by National, Liberal and One Nation politicians.
The most high-profile casualty of the citizenship crisis was Nationals leader Barnaby Joyce, also a Kwaussie, who was re-elected to the seat of New England on Saturday.
Dr Laugesen said: "In a time of covfefe, fake news, and tweetstorms, the Australian National Dictionary Centre has looked for a word of the year that is both lexically interesting and Australian.
"Kwaussie was used to describe the most high-profile casualty of the crisis, Deputy Prime Minister and National Party leader Barnaby Joyce.
"He revealed to parliament in August that, despite being born and bred in country New South Wales, he was also a New Zealander by descent."
Other contenders for word of the year included "jumper punch", referring to an illegal punch disguised as the action of grabbing hold of an opponent's jumper, usually in football, "postal survey", "robodebt", "WAxit" and "Makarrata", a Yolgnu word for agreement.
The first evidence of Kwaussie was found in a 2002 New Zealand newspaper article on Russell Crowe, Dr Laugesen said
The 2017 word of the year and shortlist were selected by the editorial staff of the Australian National Dictionary Centre, which with Oxford University Press publishes the Australian National Dictionary of words and phrases unique to Australia.
WORDS OF THE YEAR:
2017 - Kwaussie: a person who is a dual citizen of Australia and New Zealand, a New Zealander living in Australia or a person of Australian and New Zealand descent;
2016 - democracy sausage: a barbecued sausage served on a slice of bread, bought at a polling booth sausage sizzle on election day;
2015 - sharing economy: an economic system based on sharing of access to goods, resources, and services, typically by means of the Internet;
2014 - shirtfront: in figurative use, to challenge or confront a person;
2013 - bitcoin: a type of digital crypto-currency in which transactions can be performed without the need for a central bank; a unit of this currency.