Forbidden City an area of Beijing (Peking) containing the former imperial palaces, to which entry was forbidden to all except the members of the imperial family and their servants.
The name Forbidden City is also given to Lhasa in Tibet, which as the centre of Tibetan Buddhism was closed to foreign visitors until the 20th century.
the forbidden degrees the number of steps of descent from the same ancestor that bar two related people from marrying.
forbidden fruit the fruit forbidden to Adam in the garden of Eden; with reference to Genesis 2:17. The term forbidden fruit, recorded from the mid 17th century, often implies its attraction.