A firebox is a part of a fireplace or a stove where the fire is made.
A firebox can make people think of warmth, cooking, and comfort.
Examples:
The firebox is where we put the wood to make a fire.
The firebox in our fireplace is big.
She added more wood to the firebox.
The cat likes to sit in front of the firebox.
The firebox in the old house was as big as a car!
We roasted marshmallows in the firebox.