What is the definition or description of: coated tongue?

Surface goo.: Coated tongues occur for various reasons, such as fungal growth, heavy bacterial growth or simply deep colored food and drink coloring the surface. It occurs on the top of the tongue.

Film on tongue: The normal tongue is generally light pink with visible papillae, which resemble the bristles on your toothbrush. A coated tongue usually has a white to yellowish covering or thickness to it. It can look like a thin layer of tapioca on the tongue. If you brush your tongue regularly, you will get rid of that thickness and a pink tongue will greet you in the mirror.