noun

• (slang, vulgar, derogatory, offensive, ethnic slur) A person of (South) East Asian descent (originally revolutionaries of the Katipunan then generally to any native of the Philippines, after the enemy and collaborators hid amongst them), but now especially:
  "A few days later he had a 'damned good party' at NORMASH, drinking brandy, and he then 'beat up a Gook [Korean] village.' This resulted in an 'awful hangover all day', […] Later, he walked back to his unit, alone at three o'clock in the morning, having 'swiped a Gook torch.'"
• (slang, vulgar, derogatory, offensive, ethnic slur) A person of (South) East Asian descent (originally revolutionaries of the Katipunan then generally to any native of the Philippines, after the enemy and collaborators hid amongst them), but now especially:
  "Of course, I've got so many confirmed kills I lost count. Nobody believes me because the gooks drag off their dead."
• (dated, derogatory) A foreigner (to the speaker), especially the (enemy) natives of a place the speaker's military is at war with or in.
  ""Haiti is a country with a history, […]" "but how about the Marines, and the gendarmerie; aren't they on the job?" […] "You know darn well a civilian can't get away with handling a gook like a Marine can; […]""
• (dated, derogatory) A foreigner (to the speaker), especially the (enemy) natives of a place the speaker's military is at war with or in.
  ""But shit, man, don't we do a fucking good job of it. Jesus, we slew long gooks this last trip," quipped Mark."

noun

• (informal) Grime or mud.
  ""Roost No More" was a yellow gook that Joe's people would spread around, for a fee, on the ledges of houses and commercial buildings plagued by pigeons."

noun

• (slang) A dull or hapless person.
  "the poor old gook was spitting blood"

noun

• (Cornwall) A bonnet (headwear).
  "Some say 'Mar Teazer do live in pattens and gook; must go to bed in 'em I'm thinking!"