Media playback is unsupported on your device Media caption Watch how Chlöe Swarbrick shuts down heckler

A 25-year-old New Zealand politician has admitted making "some people very mad" by using a viral phrase in parliament.

Chlöe Swarbrick told an older lawmaker "OK boomer" after they interrupted her speech on climate change.

There was little reaction in parliament but she soon began trending online. She has also been accused of ageism.

What does 'OK boomer' mean?

A "boomer" is shorthand for a baby boomer - someone born between 1946 and 1964.

In internet parlance, "OK boomer" is a derogatory phrase used primarily by the next generations to show their indignation towards older people deemed indifferent to their concerns. It is used widely on platforms like Twitter and TikTok.

"Boomer is a state of mind," Ms Swarbrick told Stuff.

"I think you can see from the way that that meme has evolved that it is symbolic of the collective frustration that young people in particular feel to placing evidence in fact time after time in the debate and in the argument and being met with dogma," she said.

She also wondered whether by using the phrase so publicly she had inadvertently killed it off.

Why did Ms Swarbrick say 'OK boomer'?

Ms Swarbrick was commenting on the Zero Carbon bill, which aims to reduce net carbon emissions in New Zealand to zero by 2050, when she used the phrase.

"Mr Speaker, how many world leaders, for how many decades have seen and known what is coming but have decided that it is more politically expedient to keep it behind closed doors. My generation and the generations after me do not have that luxury," she said.

"In the year 2050, I will be 56 years old. Yet, right now, the average age of this 52nd Parliament is 49 years old."

At this point in her speech, she was interrupted by an older member of parliament, reported to be opposition spokesman for climate change, Todd Muller.

Ms Swarbrick paused, gestured with her right hand and said: "OK boomer."

The zero carbon bill at the centre of the debate was voted into law on Thursday, with historic cross-party support.

What reaction has there been?

On social media, the Green MP - elected in 2017 - has been hailed as a "queen" for using the term. But some critics see "OK boomer" as ageist.

Fellow New Zealand lawmaker Christopher Bishop expressed that "unpopular and non-woke opinion" in a tweet.

Mr Muller, on the other hand, wondered how long Ms Swarbrick would remain a "millennial force for change".

Skip Twitter post by @toddmullerBoP I’m wondering whether in 2050 when @_chloeswarbrick hits her mid fifties, will she still be the millennial force for change or will she quietly reflect that those Gen X’s knew a thing or two. I of course will be very focused on the next cup of tea.😂 https://t.co/1LufTzKxjF — Todd Muller MP (@toddmullerBoP) November 6, 2019 Report

In a post on Facebook, Ms Swarbrick responded to her critics, albeit with more than a hint of sarcasm.

"Today I have learnt that responding succinctly and in perfect jest to somebody heckling you about *your age* as you speak about the impact of climate change on *your generation* with the literal title of their generation makes some people very mad," she wrote.

"So I guess millennials ruined humour. That, or we just need to pull ourselves up by our bootstraps and abstain from avocados."