A simple example of a polarized transverse wave is vibrations traveling along a taut string (see image); for example, in a musical instrument like a guitar string. Depending on how the string is plucked, the vibrations can be in a vertical direction, horizontal direction, or at any angle perpendicular to the string.
Commission on Narcotic Drugs considers future of drug control. 14 March 2008 - The 51 st session of the annual Commission on Narcotic Drugs (CND) wrapped up today.
More often though, people are referring to legal classifications when they use the term narcotic as a drug which is a scheduled substance. Under the Federal definition, tramadol is not a narcotic, although some states have made it a schedule IV drug.