The term CODEINE SOURCE can be broken down into four crossword solutions: OPIUM (5 letters), ANODYNES (8 letters), OPITATES (7 letters), and OPIATE (6 letters). OPIUM is a narcotic drug derived from the poppy plant, which has been used for centuries as a pain reliever and sedative. Anodynes are drugs that reduce or eliminate pain. Opiates are drugs derived from OPIUM, and OPIATE is another name for an opioid, a type of drug that acts on the nervous system to relieve pain. Codeine is an OPIATE that is used to treat mild to moderate pain.