(/ˌbæɡəˈtɛl/)
Noun
1. A trifle; an unsubstantial thing.
2. A short piece of literature or of instrumental music, typically light or playful in character.
…He said later that he wanted his language to be “unlimitedly rich, flexible, full of every ‘bagatelle’ that gives life to language,” but, above all, he wanted it to be easy to learn, and that is how he promoted it.
From the post: The dream of Esperanto bringing about world peace
Source: A language to unite humankind (newyorker.com)