Decay is a word that refers to the gradual deterioration or destruction of something over time. It can be used to describe everything from organic matter to human-made structures. Some synonyms for decay include rot, decomposition, corrosion, disintegration, erosion, and decline. Each of these words has a slightly different connotation and can be used to describe decay in different contexts. Rot often refers to the breakdown of organic matter, while corrosion is typically used to describe the rusting of metal. Disintegration may be used to describe the crumbling of a structure, while erosion is commonly used in reference to the gradual wearing away of soil or rock. Regardless of the specific synonym used, decay implies a sense of loss or destruction over time.