An animal is referred to as a herbivore if it has developed physically and physiologically to eat mostly plant material, such as foliage or marine algae.
Because plant materials are more difficult to digest than animal prey, most herbivores have mutualistic gut flora that aid in this process. This flora is made up of bacteria or protozoans that consume cellulose.
Herbivorous animals often have mouthparts adapted to rasping or grinding, depending on their natural plant diet.
Examples - parrots, butterflies, cows, buffalo, grasshoppers, etc.
Plant:
The category of birds known as parrots falls within the category of herbivores.
All plant parts, such as leaves, stems, fruits, etc., are included in the diet of a herbivore.