noun
tongue coating; fur on the tongue
Medical and everyday term for the whitish or yellowish coating that can appear on the tongue.
風邪をひくと舌苔が厚くなることがある。
When you catch a cold, the coating on your tongue can become thicker.
舌苔が気になるなら、舌ブラシを使うといいですよ。
If you're concerned about tongue coating, using a tongue brush is a good idea.