The Collaborative International Dictionary of English v.0.48:
Forbidding \For*bid"ding\, a. Repelling approach; repulsive; raising abhorrence, aversion, or dislike; disagreeable; prohibiting or interdicting; as, a forbidding aspect; a forbidding formality; a forbidding air. Syn: Disagreeable; unpleasant; displeasing; offensive; repulsive; odious; abhorrent. -- For*bid"ding*ly, adv. -- For*bid"ding*ness, n. [1913 Webster]