Noun

1. A rack; a grid of wire or a sheet of material with a pattern of holes or slots, usually used to protect something while allowing the passage of air and liquids. Typical uses: to allow air through a fan while preventing fingers or objects from passing; to allow people to talk to somebody, while preventing attack.
2. On a vehicle, a slotted cover as above, to protect and hide the radiator, while admitting air to cool it.
3. A device comprising a source of radiant heat and a means of holding food near it, to cook it; a barbecue; a griddle.

   I put some peppers and mushrooms on the grill to go with dinner.

Verb

1. To cook food on a grill; to barbecue.

   Why don't we get together Saturday and grill some burgers?

2. To interrogate; to question aggressively or harshly.

   The police grilled him about his movements at the time of the crime.