1. The person who holds the position of head of state in England; Also called: pm, premier.
2. The position of the cabinet minister who is in charge of government affairs; Also called: pm, premier.
Or premier; Head of a parliamentary government, usually the leader of the largest party. In countries with an executive president, the prime minister is of lesser standing, whereas in those with dual executives, such as France, power is shared with the president.
The first prime minister in Britain is usually considered to have been Robert Walpole, but the office was not officially recognized until 1905. In some countries, such as Australia, a distinction is drawn between the prime minister of the whole country and the premier of an individual state.