This is when a woman swallows a man's load, except with a few of his pubic hairs to boot. When the load "slides" down the hatch, the pubic hair will tickle her throat. She then will make a gurgling noice that will resemble a sound that Chewbacca would make. Thus making it a Wookie Slider.
"After the wedding reception, I have every intention on giving my new bride the hairiest Wookie Slider this side of the Mississippi River!"