BOOT

• boot [countable]
• 1 a type of shoe that covers your whole foot and the lower part of your leg [↪ Wellington]:
• hiking boots
• a pair of boots
• 2 British English an enclosed space at the back of a car, used for carrying bags etc [= trunk American English]
• The new model has a bigger boot.
• 3

   the boot

  informal when someone is forced to leave their job [= the sack; ↪ dismiss]:
• The chairman denied that he had been given the boot.
• He should have got the boot years ago.
• 4

   to boot

  in addition to everything else you have mentioned:
• She was a great sportswoman, and beautiful to boot.
• 5

   put the boot in

  British English informal
• a) to criticize or be cruel to someone who is already in a bad situation
• b) to attack someone by kicking them repeatedly, especially when they are on the ground
• 6

   the boot is on the other foot

  British English used to say someone who has caused problems for other people in the past is now in a situation in which people are causing problems for them
• 7 American English a metal object that the police attach to one of the wheels of an illegally parked car so that it cannot be moved [= wheel clampBritish English]

• ➔ be/get too big for your boots

   at big1 (14)

   ; ➔ lick somebody's boots

   at lick1 (7)

   ; ➔ tough as old boots

   attough1 (2)

Definition from the Longman Dictionary of Contemporary English
Advanced Learner's Dictionary.