A Dictionary of Music and Musicians/Arabesque
ARABESQUE (Germ. Arabeske). Originally an architectural term applied to ornamentation in the Arabic style, whence its name. (1) The title has been given, for what reason is not very clear, by Schumann to one of his pianoforte pieces (op. 18), which is written in a form bearing some analogy to that of the rondo, and it has been since occasionally used by other writers for the piano. (2) The word 'Arabesque' is sometimes used by writers on music to express the ornamentation of a theme. Thus Dr. Hans von Bülow, in his edition of Beethoven's sonatas, in a note on the adagio of the sonata in B♭, op. 106, speaks of the ornaments introduced at the return of the first subject as 'diese unvergleichlich seelenvollen Arabesken'—these incomparably expressive Arabesques.
[ E. P. ]