noun

• (Ireland) A garda; a police officer.
  "The Garda Regulations 1924 required a candidate for appointment as a guard to be able to produce satisfactory references as to his character"
• (military) A squad responsible for protecting something.
  "The president inspected the guard of honour."
• (military) A squad responsible for protecting something.
• (Australia) A panel of a car that encloses the wheel area, especially the front wheels.
  "Another possible way is to go for a lower profile tyre (50 series). This effectively lowers the distance of the tyre wall away from the guard (not by much though and generally, the lower the profile, the wider the tyre so the tyre may stick out more as well)."

verb

• (transitive) To protect from danger; to secure against surprise, attack, or injury; to keep in safety; to defend.
  "For Heaven still guards the right."
• (transitive) To keep watch over, in order to prevent escape or restrain from acts of violence, or the like.
  "Guard the prisoner."
• (ambitransitive) To watch by way of caution or defense; to be cautious; to be in a state or position of defense or safety.
  "Careful people guard against mistakes."
• (transitive) To protect the edge of, especially with an ornamental border; hence, to face or ornament with lists, laces, etc.
  "The body of your discourse is sometime guarded with fragments, and the guards are but slightly basted on neither."