first minister vs minister-president

first minister

noun
  • The principal minister of a ruler or state. 

  • A leader of a devolved government such as Scotland, Wales, or Northern Ireland. 

  • The prime minister or a provincial or territorial premier. 

minister-president

noun
  • The head of government in a number of European countries or subnational governments, in which a parliamentary or semi-presidential system of government prevails, who presides over the council of ministers. 

How often have the words first minister and minister-president occurred in a corpus of books? (source: Google Ngram Viewer )