Which term refers to a musical texture with one main melodic line supported by accompaniment?

The term that describes a musical texture featuring one main melodic line supported by accompaniment is homophony. In this texture, the dominant melody takes precedence, while other voices or instruments provide harmonic support that enhances and complements the melody. This is commonly found in many popular music genres, where a singer may be accompanied by chords played on a guitar or piano.

In contrast to homophony, polyphony consists of two or more independent melodic lines that are intertwined, creating a complex, interwoven sound. Heterophony involves the variation of a single melody played by different instruments or voices, producing a less structured texture. Monophony, on the other hand, is characterized by a single melodic line without any accompaniment, which can be sung or played by one or more performers in unison. Understanding these distinctions clarifies why homophony is the term applicable to the situation described in the question.