(1):

(n.) Ornamental work, formerly with grains or breads, but now composed of fine wire and used chiefly in decorating gold and silver to which the wire is soldered, being arranged in designs frequently of a delicate and intricate arabesque pattern.

(2):

(a.) Relating to, composed of, or resembling, work in filigree; as, a filigree basket. Hence: Fanciful; unsubstantial; merely decorative.