What is "arabeske"

Robert Schumann wrote his Arabeske in C major, Op. 18 in 1839 when he was 29 years old, dedicating it to Frau Majorin Friederike Serre auf Maxen, to whom he also dedicated his Blumenstück in D-flat, Op. 19. In the autumn of 1838 Schumann had left Leipzig for Vienna. His relationship with Clara Wieck had reached a point of no return, as her father vehemently opposed anything that might interfere with his daughter's career as a pianist and strongly disapproved of Schumann as a possible son-in-law. Geographically yet not emotionally detached from Clara, he was able to communicate with her only through letters and in his own music. This has been proposed as an explanation for this work, which alternates passages of wistful longing with more robust, declamatory episodes.