A mark often left on the front of a pair of underwear, usually the result of leftover male ejaculate.
After a pleasurable night of adultery with my wife's sister, the only evidence that got me busted was a couple of overlooked squid marks on my boxers, and her dress.
by Briggsyl March 30, 2008
the scottish version of skid mark. It' sthe little shit stain you may find in the seat of your underwear after a rigorous session of pinching white castle sliders and not geting all the little pueblos.
"you've a fucking squidmark, go wipe your bottom!"
by so sayeth the lexicon October 03, 2003