R/woosh is usually a comeback reply to someone who did not understand a joke and seriously responds to the joke. 

People have been making jokes for centuries, but jokes in the past were usually told through the help of facial expression, tone, or timing. In our internet age, we have the ability to make jokes without them, and it can lose its meaning along the way. People misinterpret jokes on the internet more often, or miss any sarcasm made through our texts, so it isn’t a surprise that there is a subreddit dedicated to catching any of it in action.

People usually don’t reply back, or they “r/whooosh” the person that “r/whooosh”ed them by claiming their serious reply was a joke itself. There are many ways to reply back, but there’s no “correct” way of doing so. 

Origins: The origin of this phrase comes from the subreddit (https://www.reddit.com/r/woosh/) and sometimes leaks through other social media platforms other than reddit. It was created on November 15, 2009.

It’s usually redittors or people who know of this subreddit that use it.