accompaniment
Something that goes with something else to support it.
An accompaniment is something that goes along with something else to complete it or make it better. In music, an accompaniment is the background music that supports the main melody. When a pianist plays chords while a violinist performs the main tune, the piano is providing the accompaniment. When singers perform with a band, the instruments create an accompaniment that makes the voices sound fuller and richer.
Just like a good companion makes a journey more enjoyable, a good accompaniment enhances whatever it joins. A meal might come with side dishes as accompaniments: a grilled chicken breast might be served with roasted vegetables and rice to complete the dinner.
In everyday situations, you might hear someone say their laughter was the accompaniment to a funny story, or that thunder served as the accompaniment to heavy rain. The word suggests a supporting role rather than the starring one. The accompaniment matters, but it works in the background, making the main thing better without trying to steal the spotlight.