nocturne (n.)

1851, "musical composition of a dreamy character," properly instrumental, from French nocturne, literally "composition appropriate to the evening or night," noun use of Old French nocturne "nocturnal," from Latin nocturnus (see nocturnal). The style and the name are said to have originated c. 1814 with Irish-born composer John Field, who wrote many of them, in a style that Chopin mastered in his own works, which popularized the term. But Field's work seems to have been appreciated in German and French publications before it came to attention in England in 1851.