Main entry: notion, whim, whimsey, whimsy
Definition: an odd or fanciful or capricious idea
Usage: the theatrical notion of disguise is associated with disaster in his stories; he had a whimsy about flying to the moon; whimsy can be humorous to someone with time to enjoy it
Main entry: impulse, whim, caprice
Definition: a sudden desire
Usage: he bought it on an impulse