fool notion

I had some fool notion of being a lawyer, and mother, I can see now, was all for having me a preacher of her faith.

"Walt, say something to get him out of that fool notion," pleaded the old sailor, helplessly.

"It's a fool notion and I ain't going to let you do it," the captain stormed, but Charley only grinned, cheerfully.

What does Jem do, when he thinks things over, but get some fool notion in his head about not coming back here and pushing me out.

Turning to Wade he asked: "What made ye take sich a fool notion as this, boy?"