capriccio

1. a lively piece of music, typically one that is short and free in form.

   its four acts contain a number of capriccios and chorales

2. a painting or other work of art representing a fantasy or a mixture of real and imaginary features.

   two capriccios by de la Joue which fitted 18th century frames

early 17th century (denoting a sudden change of mind): from Italian, literally ‘head with the hair standing on end’, hence ‘horror’, later ‘a sudden start’ (influenced by capra ‘goat’, associated with frisky movement), from capo ‘head’ + riccio ‘hedgehog’.