Romantic body language and/or
passionate physical interaction between lovers in full public view. When over-used or too graphic, can be indicative of an insecure couple in an unstable relationship. PDA exhibitionism is used by many couples to prove their love to onlookers, and to elicit envy.
"Look at those two douchebags and their tacky public displays of affection, playing tonsil hockey over there like a couple of ferrets in heat. Get a room!