a cap·pel·la I. adverb alsoa ca·pel·la\ˌäkəˈpelə, ˌȧ-\ Etymology: Italian a cappella in chapel or choir style 1.: in a style marked by the absence of instrumental accompaniment < sing a cappella > 2.obsolete: in alla breve time II. adjective alsoa capella\| ̷ ̷ ̷ ̷| ̷ ̷ ̷ ̷\ 1.: unaccompanied by instruments : marked by or specializing in unaccompanied singing < an a cappella choir > 2.obsolete: alla breve