noun

• (literature, music) A short piece of literature or of instrumental music, typically light or playful in character.
  "One afternoon in 1920. a young pianist sat down in a shuttered room in the capital of defeated Germany and played a Bagatelle by Beethoven."
• (uncountable) A game similar to billiards played on an oblong table with pockets or arches at one end only.
  "For some time they did nothing save box, but at last they went down to the bagatelle room, and played bagatelle for a bit. They marked this advance in civilization by prodding holes in the ceiling with the bagatelle cues, which gave the ceiling the appearance of a cloth target after a Gatling gun had been shooting at it."
• (uncountable) Any of several smaller wooden tabletop games developed from the original bagatelle in which the pockets are made of pins.

verb

• (intransitive, rare) To meander or move around, in a manner similar to the ball in the game of bagatelle.
  "Admittedly Mané’s strike did rebound off a post as the ball bagatelled around the home area. It was characteristically cleared before Roberto Firmino could redirect the fall out beyond Henderson."
• (transitive, rare) To bagatellize; to regard as a bagatelle.
  "That Saddam Hussein announced his intentions to destroy Israel a long time ago was either ignored or bagatelled. “We just didn't have time to address the threat to Israel,” explained Brigitte Erler on the eve of a large peace demonstration in Bonn."