a banquet (=formal dinner) held in the Guildhall, London, every year after the new Lord Mayor of London has been elected. Many important people are invited to this banquet, including the Prime Minister, who makes a speech to mark the occasion.
Definition from the Longman Dictionary of Contemporary English Advanced Learner's Dictionary.
Dictionary pictures of the day
Do you know what each of these is called?
Click on any of the pictures above to find out what it is called.