notion
[ noh-shuhn ]
a general understanding; vague or imperfect conception or idea of something
USE 1
Many people have a notion of what success looks like, but it can vary greatly from person to person.
USE 2
He had a notion that starting a business would be easy, but reality quickly proved otherwise.
USE 3
The notion of traveling the world excited her, even though she hadn’t planned any details.
