bagatelle n.

1630s, "a trifle, thing of no importance," from French bagatelle "knick-knack, bauble, trinket" (16c.), from Italian bagatella "a trifle," which is perhaps a diminutive of Latin baca "berry," or from one of the continental words (such as Old French bague "bundle") from the same source as English bag (n.). As "a piece of light music," it is attested from 1827.