accompaniment vs rounding-off

accompaniment

noun
  • A part, usually performed by instruments, that gives support or adds to the background in music, or adds for ornamentation; also, the harmony of a figured bass. 

  • That which accompanies; something that attends as a circumstance, or which is added to give greater completeness to the principal thing, or by way of ornament, or for the sake of symmetry. 

rounding-off

How often have the words accompaniment and rounding-off occurred in a corpus of books? (source: Google Ngram Viewer )