sedative

Having a soothing, calming, or tranquilizing effect; reducing or relieving anxiety, stress, irritability, or excitement.

An agent or a drug having a soothing, calming, or tranquilizing effect.

Tending to calm, tranquilize, or soothe; specifically, in medicine, having the power of allaying or assuaging irritation, irritability, or pain.

Whatever soothes, allays, or assuages; specifically, a medicine or a medical appliance which has the property of allaying irritation, irritability, or pain.

Tending to calm, moderate, or tranquilize.