opiumBrE/ˈəʊpiəm/NAmE/ˈoʊpiəm/noun[U]apowerfuldrugmadefromthejuiceofatypeofpoppy illegally for pleasure and can become addicted (= akindofflower), usedinthepastinmedicinestoreducepainandhelppeoplesleep. Somepeopletakeopiumillegallyforpleasureandcanbecomeaddictedtoit鸦片