Chlöe Swarbrick, a 25-year old climate MP was presenting her climate change case to the New Zealand parliament, and was heckled by an older audience member. Without missing a beat, she acknowledged and dismissed the challenger with a pithy “Ok, Boomer.”

The recording has since gone viral, inspiring everything from merchandise to Vogue articles. While the incident isn’t the source of the phrase “Ok, Boomer”, today it is the most well known manifestation. So what does the phrase mean? If you are inclined to more colorful language, see Urban Dictionary. But the meaning is obvious on its face — Gen Z is dismissing utterly and without consideration the judgment and protestations of society’s elders on multi generational issues like economics, climate change, and social norms.