(In the UK) the chief usher of the Lord Chamberlain’s department of the royal household, who is also usher to the House of Lords.A message from Her Excellency the Governor-General desiring the immediate attendance of honourable members in the Legislative Council Chamber was delivered by the Gentleman Usher of the Black Rod....
The Gentleman Usher of the Black Rod announced the arrival of Her Majesty's Commissioners.
‘We in parliament were all very impressed by the way Black Rod handled the funeral.’
Origin
Mid 17th century: so named because of the black wand carried as a symbol of office.