Which is not considered to be an accessory organ of the digestive system?

The spleen is not considered to be an accessory organ of the digestive system.

The accessory organs of the digestive system include the tongue, salivary glands, liver, pancreas, and gallbladder. These organs help with the digestion of food, but are not part of the digestive tract itself. The spleen is a separate organ that is part of the lymphatic system and is involved in the production and storage of blood cells.