What does moral decay mean?

Moral decay is a pejorative term referring to a perceived gradual weakening of standards of right and wrong, particularly within a society (e.g., “The party’s leader said he would ‘fight against the moral decay that lies at the heart of the country’s problems’”).

On a related note, if you’re unsure whether the correct word is moral or morale, bear in mind that you can only use “morale” as a noun.

QuillBot’s free Paraphraser will help you to find alternative ways of expressing “moral decay” that fit the context of your specific text.