This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

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

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

n. An agent or drug that sedates, having a calming or soothing effect, or inducing sleep.

adj. Calming, soothing, inducing sleep, tranquilizing

adj. Tending to calm, moderate, or tranquilize.

n. A remedy which allays irritability and irritation, and irritative activity or pain.

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

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

adj. tending to soothe or tranquilize

n. a drug that reduces excitability and calms a person

"Alcohol is a short-term sedative but may induce shallow sleep and less overall sleep time."

depressant   

stimulating    exciting   

sedative water    sedative salt    cardiac sedatives   

assuaging    assuasive    soothing    calmative    calmant    downer    sleeping pill    anxiolytic    soporific    depressant   

diuretic    stimulant    tonic    anodyne    aphrodisiac    depressant    antitumor    analgesic    painkiller    anesthetic