“A Pyrrhic victory” means:

The idiom "A Pyrrhic victory" means "A victory won at too great a cost." This phrase originates from King Pyrrhus of Epirus, who, after defeating the Romans in 279 BC, suffered such heavy losses that he famously remarked, "If we are victorious in one more battle with the Romans, we shall be utterly ruined." It describes a success that comes with such devastating losses or sacrifices that it feels more like a defeat, making the achievement hollow or unsustainable.

• "A decisive win" implies a clear and overwhelming victory without significant drawbacks, which is the opposite of a Pyrrhic victory.
• "An easy win" suggests minimal effort or cost, directly contradicting the idiom's meaning.
• "A loss disguised as win" implies deception or a misunderstanding of the outcome, whereas a Pyrrhic victory is genuinely a win, albeit a costly one.