腰抜かす こしぬかす Meanings Godan verb to dislocate one's back See also: 腰を抜かす (こしをぬかす). to be unable to stand up due to fear or surprise; to lose one's legs Kanji 腰 waist. Read as こし. 抜 pull out. Read as ぬかす. Jinuma: Japanese Dictionary · Word lists