caprice

noun5

1. •
   An impulsive, seemingly unmotivated action, change of mind, or notion.

   • She is said to be the finest swordswoman on the Continent. Yet, notwithstanding her caprices, she is a noble-minded woman. — 1899
2. •
   An unpredictable or sudden condition, change, or series of changes.
3. •
   A disposition to be impulsive.

   • Yet, Britain, vvhence this Caprice of thy Sons, / VVhich thro' their various ranks vvith fury runs? / The cause is plain, a cause vvhich vve must bless; / For Caprice is the Daughter of Success, […] — 1726
4. •
   A capriccio.
5. •
   A brief romance.

   • The only difference between a caprice and a life-long passion is that a caprice lasts a little longer. — 1891