Webster's Revised Unabridged Dictionary · 1913

Forbidden

Forbidden , adjective

Prohibited; interdicted.
I know no spells, use no forbidden arts. — Milton
Collocations (1)
Forbidden fruit (Botany) , (a) Any coveted unlawful pleasure, -- so called with reference to the forbidden fruit of the Garden of Eden. A small variety of shaddock (Citrus decumana). The name is given in different places to several varieties of Citrus fruits.