1.
decline, on the wane, going downhill
A state of declining fortune, popularity, or power. Used to describe a person, business, or entity that has passed their peak and is losing status or relevance.
Usage
An informal, slightly blunt word. Carries a negative connotation and is not used in formal speech. Often used about public figures, businesses, or trends that have lost momentum. Can sound harsh when used about a person directly.