What is the meaning of Chimerical?

Of or pertaining to a chimera.

Being a figment of the imagination; fantastic (in the archaic sense).

Inherently fantastic; wildly fanciful.

Resulting from the expression of two or more genes that originally coded for separate proteins.

Impossible to physically produce due to having an impossibly-high saturation or luminosity, but viewable by overlaying an afterimage and a suitably-colored physical image.

Source: wiktionary.org