accompaniment

/ə-ˈkəm-pə-nē-mənt/

accompany-ment, on the model of French accompagnement, going back to Old French acompaignement "feudal power-sharing contract," derivative of acompaigner "to accompany

noun

  1. an instrumental or vocal part designed to support or complement a melody

  2. an addition (such as an ornament) intended to give completeness or symmetry to something : complement

  3. an accompanying situation or occurrence : concomitant

sang the song with a piano accompaniment

idiom

  1. while corresponding music is played

  2. at the same time (something else) is happening

She sang the song to the accompaniment of a piano.