knight

a knight in shining armour an idealized or heroic person, especially a man who comes to the rescue of a woman in distress or in a difficult situation.

☞ This expression, a variant of which is a knight on a white charger, is often used ironically of someone who presents himself in this guise but is in fact inadequate to the role. Compare with a white knight (atwhite).

knight of the road a man who frequents the roads, for example a travelling sales representative, lorry or taxi driver, or tramp.

☞ Originally, in the mid 17th century, this phrase was ironically applied to a highwayman.

knight of the shires a British Conservative member of parliament who has the title 'Sir' and sits for a rural constituency, typically one of long service and with a high place in the party hierarchy.

2011Daily Telegraph During the negotiations for entry, a Tory knight of the shires, Sir Derek Walker-Smith, was one of the few to draw attention to the significance of Article 3, Paragraph H of the Treaty of Rome.

a white knight: seewhite.