Homonym: stain (Mark)
A "stain" is a mark or discoloration that can occur on various surfaces, such as fabric, wood, or walls. Stains are often caused by substances like food, drink, or ink that penetrate the material, making them difficult to remove. Different types of stains require specific cleaning methods and products for effective removal.
Stains can be classified into two main categories: water-based and oil-based. Water-based stains, such as those from juice or coffee, can often be cleaned with soap and water. In contrast, oil-based stains, like grease or paint, may need solvents or specialized cleaners to effectively eliminate them.