notion

/ˈnəʊʃən/

Mental apprehension of whatever may be known, thought, or imagined; idea, concept.

A sentiment; an opinion.

Sense; mind.

An invention; an ingenious device; a knickknack.

Yankee notions

Any small article used in sewing and haberdashery, either for attachment to garments or as a tool, such as a button, zipper, or thimble.

Inclination; intention; disposition.

I have a notion to do it.