Fantastical
Part of speech: adjective
Definition: of or pertaining to fantasy fanciful or whimsical fantastic
Fantastic
Part of speech: adjective
Definition: Existing in or constructed from fantasy; of or related to fantasy; fanciful.Not believable; implausible; seemingly only possible in fantasy.Wonderful; marvelous; excellent; extraordinarily good or great (used especially as an intensifier).
Example sentence: When I was four I joined a group of girls who were talking about their party dresses. I thought they were imagining, so I imagined a fantastic pink velvet dress with lots of jewels. But they were simply describing what they actually wore, and they had utter contempt for my obvious fiction. After that, I never joined a group again.