It's amazing how those two seemingly innocuous words have caused a ripple of anger, disgust and frustration across the globe.
These two words have been adopted by Generation Z (people born in the late 90s and younger) and millennials (people born between 1980 and the mid-90s) as a way to mock older people when they express views perceived as close-minded, out of touch, or old-fashioned.
It's an umbrella term for anyone exhibiting the kind of behaviour young people associate with old fogeys - the people who can't keep up with the times and bury their heads in the sand defiantly refusing to accept the world is changing.
You'll find an onslaught of "Okay, boomer" responses to anyone that: Posts a comment on Facebook denying climate change; writes an online review lambasting a supermarket chain when forced to use a self-service machine; shares a link to an obviously false news story; or cracks a tasteless joke about marriage being akin to castration.
They're all the kinds of behaviour that younger generations have come to associate with baby boomers - and when someone gets angry at a young person saying "okay, boomer", that's also expected behaviour, and therefore part of the joke.
Us millennials and the younger Gen-Zers are used to being harassed by older generations for our perceived shortfalls.
We're the generations who grew up being handed medals just for taking part in a race - medals presented to us proudly by the gushing adults who then mocked us for needing praise at every turn.
We're the ones who watched in dismay as our awesome adventure playgrounds got dismantled in front of our eyes and replaced with boring plastic tunnels all a carefully calculated distance off the ground by health and safety-obsessed adults who then berated us for growing up averse to taking risks.
We grew up with parents and grandparents who told us how important it was to get a good education, who then laughed behind their hands at the silly young people wracking up piles of student loan debt instead of getting a real job.
We get called snowflakes by older people who then get mad at an "Okay, boomer" comment.
That's what makes it so funny.
Laugh all you want at how silly we can be - but don't dish it out if you can't take it.