Screaming was a quality that could be applied to magical weapons.
When active, the weapon made a low and irritating humming noise. It changed to a painful screaming when it struck a target.
It inflicted sonic damage, even within the area of a silence spell. It had no special effect on creatures with enhanced hearing, but it was especially annoying to them.
If it was applied to ranged weapons, the effects applied to their ammunition.
It required a shout or sound burst spell to enchant a screaming weapon. 
- ↑ Sean K. Reynolds, Duane Maxwell, Angel McCoy (August 2001). Magic of Faerûn. (Wizards of the Coast), p. 140. ISBN 0-7869-1964-7.