Definition for Analgesic
From Biology Forums Dictionary
An analgesic (also known as a painkiller) is any member of the group of drugs used to relieve pain (achieve analgesia). Analgesic drugs act in various ways on the peripheral and central nervous systems; they include paracetamol (para-acetylaminophenol, also known in the US as acetaminophen or simply APAP), the non-steroidal anti-inflammatory drugs (NSAIDs) such as the salicylates, and opioid drugs such as morphine and opium. They are distinct from anesthetics, which reversibly eliminate sensation.