Definition:
* A sudden desire or change of mind, especially one that is unusual or unexpected.
* A capricious notion or fancy.
* A sudden, impulsive action or decision.
Examples:
* "On a whim, she decided to quit her job and travel the world."
* "He bought the car on a whim, without even test-driving it."
* "The new policy was implemented on the whim of the CEO."
Synonyms:
* Fancy
* Impulse
* Notion
* Caprice
* Freak
* Craving
* Vagary
Antonyms:
* Reason
* Logic
* Deliberation
* Planning
* Premeditation
Usage:
* "She acted on a whim and bought a new dress she didn't need."
* "His sudden change of heart was a complete whim."
* "The company's decision to launch the product was based on a whim."
Note:
* Whim often implies a lack of thought or consideration.
* It can be used to describe both positive and negative actions.
* When used to describe someone's behavior, it can suggest that they are unpredictable or fickle.