"Let’s go" is "고고씽"(ko-go-ssing) in Korean.
"Let's Go" is called 고고 씽 (Kogoshin) in Korea.
"고 (Go)" is in English "Go (Go)" in the "씽 (ssing)" represents the sound of "wind". English "Let's Go (가자)" words plus the sound of "Wind" to mean. Sometimes written as 고고싱.