The word **插曲** (chāqǔ) is a compound term formed through semantic combination: the character **插** means "to insert" or "thrust into," and **曲** means "song," "tune," or "melody." Literally, it refers to an "inserted song" or interlude within a larger musical or dramatic performance, such as in an opera or film. By metaphorical extension, this structural concept of an inserted element is applied to narrative and life experiences, giving the word its common figurative meaning of an "episode" or "interlude"—a brief, unexpected event or incident that occurs within the broader sequence of a story or one's life. Thus, its formation moves from a concrete musical term to an abstract, conceptual one.