Protracted
Etymology
From Latin protrahere, "to draw forth, drag out" (pro-, "forward," + trahere, "to draw, drag"), by way of its past participle protractus. The same trahere gives us "tractor" and "traction." The core image is of physically dragging something out to a greater length, applied here to time.
adjective · /proh-TRAK-tid/
Drawn out and prolonged, lasting longer than expected or desired.
What it names
The word for something stretched out well past its natural length — a protracted negotiation, a protracted illness — with a faint sense of weariness at how long it drags on.
Example
What should have been a quick sale turned into a protracted legal battle that outlasted the property’s value.
Related idea
Prolonged is fairly neutral about lengthening something; protracted leans negative, implying the extension is tedious, unwelcome, or unnecessary.