Messy J Posted in M Best definition Messy J A PCP laced joint dipped in formaldehyde. Dude rolls a messy J in the bathroom – goes outside for a toke and starts to spew esoteric bullshit to anyone who will listen. How satisfied are you with the definition? Looking for Messy J meaning? Delighted that you discovered the greatest determine on our web site! Recently this definition was actually observed 11 times.