Gookamachook is a word that is derived from the derogatory term gook - a term used to describe Koreans. Gookamachook is a term that can be applied to any chink race (i.e. any 'nese' i.e. Chinese, Japanese, Koreanese, or Vietnamese) that looks or talks different. Generally proficient in high level math and video games and incompetent driver and looks like they just stepped off of 'the boat'.
That gookamachook over there almost hit my car because they were trying to take a picture, make a piece sign with their fingers, and play their game boy all at the same time.