GOOK
sludge, slime, goo, goop, gook, guck, gunk, muck, ooze
(noun) any thick, viscous matter
Source: WordNet® 3.1
Etymology 1
Noun
gook (plural gooks)
(slang, vulgar, derogatory, offensive, ethnic slur) A person of Far Eastern or Oceanian descent, especially a Vietnamese, Filipino, Chinese, Japanese or Korean person.
(US, derogatory) A Vietnamese insurgent in the Vietnam War, particularly a member of the Viet Cong.
(dated) A foreigner, especially an enemy soldier in wartime.
(Rhodesia, derogatory) A black insurgent in the Rhodesian Bush War.
Usage notes
• In the US, gook refers especially to a Vietnamese person in the context of the Vietnam War, and particularly to the Viet Cong. It is generally considered to be highly offensive, on par with nigger.
Etymology 2
Noun
gook (plural gooks)
(informal) Grime or mud.
Source: Wiktionary