notion
//ˈnoʊʃən//
Noun
notionSingular
notionsPlural
1
A conception or belief about something; an idea or understanding
She has a strange notion that cats can predict the weather.
2
A vague or imperfect understanding; an impression
I have only a vague notion of what happened that night.
3
A whim or fancy; a sudden desire or inclination
She had a sudden notion to travel to Paris.