From Wikipedia
I don't usually believe everything I find in Wikipedia and I am (gradually) learning to curb my, er, pen, when someone makes a slight mistake.
This little section from Wikipedia is interesting and, I think, offers a good explanation for some of the terms we all bat around here:
British English-American English
mains power- line power
earth connection- ground connection
flex/mains lead- cord
socket, power point- outlet, receptacle, socket
pin- prong or plug
In the United States, the live contact may be called live or hot. The neutral contact may be called cold, neutral, return, the grounded conductor, or (in the National Electrical Code), the identified conductor. The earth contact is called ground or the grounding conductor.
In the United Kingdom the word "line" is occasionally used to denote the live terminal or wire. This terminology derives from its being at the line voltage relative to neutral and ground, as distinct from the "phase" voltage, between lines on different phases of the supply.
Live conductors are called phases when there is more than a single phase in use. Pins are also known as prongs, contacts or terminals.
In Australia, the live contact is called active.
Since many Americans use the UK terms and vice-versa, this should all be taken with a grain of salt.
Am posting a link to the entire article - some interesting stuff there.
http://en.wikipedia.org/wiki/Domestic_AC_power_plugs_and_sockets