The definition of a has-been is a person or thing that used to be popular or helpful.
An example of a has-been is a once famous actor who no one has heard about in decades.
Informal a person or thing that was formerly popular or effective but is no longer so: a dismissive term
nounpl. has-beens Informal
One that is no longer famous, popular, successful, or useful.
- Typically said of professionals or celebrities whose prime is behind them.