Comédie mêlée d'ariettes (comedy mixed with brief arias) is a form of French opéra comique that developed in the mid 18th century following the Querelle des Bouffons dispute over the respective merits of the French and Italian styles, between serious drama and comedy in opera.
The best-known ones are Christoph Willibald Gluck's La rencontre imprévue, André Ernest Modeste Grétry's Zémire et Azor, Pierre-Alexandre Monsigny's Le déserteur and François-André Danican Philidor's Tom Jones. The form is particularly associated with the work of the librettist Louis Anseaume.
References
Comédie mêlée d'ariettes Wikipedia(Text) CC BY-SA