NCI Dictionary of Cancer Terms
The NCI Dictionary of Cancer Terms features 7,812 terms related to cancer and medicine.
Browse the dictionary by selecting a letter of the alphabet or by entering a cancer-related word or phrase in the search box.
- listen (OH-pee-ut)
- A substance used to treat pain or cause sleep. Opiates are made from opium or have opium in them. Opiates bind to opioid receptors in the central nervous system. Examples of opiates are codeine, heroin, and morphine. An opiate is a type of analgesic agent.