Merely imaginary; fanciful; fantastic; wildly or vainly conceived; having, or capable of having, no existence except in thought; as, chimerical projects.

being or relating to or like a chimera; "his Utopia is not as chimeric commonwealth but a practical improvement on what already exists"- Doublas Bush

produced by a wildly fanciful imagination; "his Utopia is not a chimerical commonwealth but a practical improvement on what already exists"- Douglas Bush