Distinction without a difference.

The phrase is used to dismiss a purported distinction as merely verbal or superficial—an attempt to draw a line between two things that, in substance, amount to the same. It often appears in legal, philosophical, and rhetorical settings where someone is accused of hair-splitting: changing labels, categories, or definitions without changing the underlying reality. As a compact piece of critical language, it functions as a check on sophistry and on arguments that rely on rebranding rather than genuine conceptual or practical difference.