The Oxford Thesaurus An A-Z Dictionary of Synonyms - notionn.

1) idea, thought, concept, conception, image, impression, general idea, (mental) picture, inkling: She has a pretty good notion of who did it. I haven't the slightest notion of what you are talking about. 2) fancy, whim, crotchet, whimsy, caprice, impulse, inclination, vagary, conceit, quirk, kink: She suddenly took a notion to fly to New York and left.