Before revision: In constitutional usage in Commonwealth realms, a ministry (usually preceded by the definite article, i.e., the ministry) is a collective body of government ministers headed by a head of government, such as a prime minister.
After revision: In constitutional usage in Commonwealth realms, a ministry (usually preceded by the definite article, i.e., the ministry) is a collective body of government ministers led by a head of government, such as a prime minister.