specialization: meaning narrows to refer to something specific
The original word mete, meaning food, encompasses all types of food. It includes vegetables, fruit, bread, candy, meat, dairy, etc. However, the new word meat only refers to the animal product. This is a change from something more general that means a variety of products to the more specific of meat only referring to the animal product.
We don't have enough information here to determine whether or not it has changed to something more or less favorable.