grobble means: All smokin’ hot chicks. This expression is derived from the “robble-grobble” sound, which was made in South Park’s crowd scenes. This is a great phrase for when you want to appear busy while spotting chicks outside your office windows. To make it easier for men to notice that a girl is coming, “grobble” can be used to indicate this. (in Community Dictionary, added by Jolie Kirk)