Based on the provided source material, Cengkok refers to specific musical patterns played by elaborating instruments within the Indonesian Javanese gamelan ensemble. These melodic formulas are structured to lead toward a sèlèh, which serves as a structural point in the music.
The execution of these patterns is governed by the rules of the pathet, the specific modal framework of the musical piece. While the subject was initially identified as a city, the source material defines Cengkok strictly as a component of Javanese musical theory and performance.