wtf Share definition Flag usually known as the internet abbr. of 'what the fuck' it might also mean 'what the flip' for those who are in the habit of not swearing. the two definations are often confused. "OMG my net jus died!" "wtf!?" wtf by Bugerme June 17, 2008 0 0 Get merch Get the wtf mug. Buy Now — $32.95 See more merch