Oh my lord. Just watch:
Love Doctor, the term you're looking for is "dap," or "fist-bump," or "fist tap"… Well, almost anything would have been better, even "respect knuckles" or the New York Times' unintentionally hilarious "closed-fisted high-five." ("Terrorist fist jab" remains some combination of wingnut fanaticism, bigotry and McCarthyism, however, and is unacceptable.) Look, it's one thing not to be hip to the current lingo, but the term you used not only does not mean what you think it means, it did not exactly come into usage recently.
Love Doctor, heal thyself. Do read up on this one (Urban Dictionary gets pretty damn explicit), and, in the immortal words from Hamlet, "Taint not thy mind."
(And yes, this is a terribly immature post.)
(Cross-posted at Blue Herald)
Update: Self-Portrait in a Screen Capture
The BH slugline says it all: