Original: The Leader of Her Majesty's Most Loyal Opposition in the United Kingdom (more commonly known as the Leader of the Opposition in the House of Commons) is the politician who leads the Official Opposition (Her Majesty's Most Loyal Opposition) in the United Kingdom.
Simplified: The Leader of the Opposition (sometimes known as the Leader of the Opposition in the House of Commons) in the United Kingdom is the politician who leads Her Majesty's Loyal Opposition.