SRD:Silence

Upon the casting of this spell, complete silence prevails in the affected area. All sound is stopped: Conversation is impossible, spells with verbal components cannot be cast, and no noise whatsoever issues from, enters, or passes through the area. The spell can be cast on a point in space, but the effect is stationary unless cast on a mobile object. The spell can be centered on a creature, and the effect then radiates from the creature and moves as it moves. An unwilling creature can attempt a Will save to negate the spell and can use spell resistance, if any. Items in a creature’s possession or magic items that emit sound receive the benefits of saves and spell resistance, but unattended objects and points in space do not. This spell provides a defense against sonic or language-based attacks.