Bible Dictionary
FOUL
Foul means defiled, impure, wicked, muddied, or polluted. It can describe unclean spirits, contaminated waters, stormy weather, or a face marked by intense weeping.
Biblical Usage
Scripture speaks of foul or unclean spirits, polluted or muddied rivers and streams, stormy weather, and a face made red by weeping. The Revised Version often replaces foul with unclean, red, stormy, or other more specific terms.