musical farting; amusing fart sounds
Archaic noun referring to the act of producing various entertaining fart sounds, likely from Edo-period humor or street performance. Not used in modern Japanese outside of historical references.
It seems there was a performance called kyokube (musical farting) in Edo-period sideshows.
Compound of 曲 (kyoku, 'music' or 'tune') and 屁 (he, 'fart'), literally 'musical fart'. The exact historical origin is uncertain, but it likely referred to a type of lowbrow entertainment in the Edo period.