Dictionary
for•bid•den
Pronunciation: (fur-bid'n, fôr-), [key]—
v.
a pp. of
forbid.
—
adj.
1. not allowed; prohibited:
a forbidden food in his religion.
2. Physics.involving a change in quantum numbers that is not permitted by the selection rules:
forbidden transition. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.