na-adjective
delusional; chimerical
Describes ideas, beliefs, or perceptions that are fanciful, unrealistic, or detached from reality. Often used in psychological or critical contexts.
彼の計画は妄想的で、実現するとは思えない。
His plan is delusional; I don't think it will come true.
妄想的な考えに取り憑かれている。
He is possessed by chimerical ideas.