A terrine is a pot or a pate
A terrine is an earthenware pot, usually oval, lidded, and having an opening cut into the top to function like the slashes made in a piecrust to vent the steam.
Terine, like marmite, is one of those words that serves for both pot and contents. A terrine is a dish of ground and chopped meat; actually a pate served from this specific dish.