IPA: /dɪsˈjuːzd/
KK: /dɪsˈjuːzd/
Not being used anymore or not occupied.
The disused railway line has become a popular walking path.
Disused → It is formed from "dis-" (meaning apart or away) and "used" (from Old French *user*, meaning to employ or utilize). The word "disused" means something that has been set apart from use or no longer employed.
Think of something that has been 'set apart' ('dis-') from being 'employed' ('used') — that's why disused means no longer in use.