misnomer

A mistake in the naming of a person or place; a misidentification.

An incorrect use of a term, especially one which is misleading; a misname.

Rewilding[…]is also a misnomer, for whether by getting rid of tens of thousands of sheep in Patagonia or introducing a living species as a surrogate for an extinct one – Sayaguesa cattle in place of aurochs in Croatia’s Velebit Mountains, for instance – rewilding requires more human intervention than its name suggests.

[…] plaintiff's misstyling himself as corporation in initial complaint constituted case of misnomer.

A term which is misleading, even if firmly established, technically correct, or both.

The name Chinese checkers is a misnomer since the game has nothing to do with China.

The word blackboard as applied to green or brown chalkboards is a misnomer but is not incorrect, as the broad sense of the word is idiomatic.

Something which is asserted not to be true; a mistaken belief, a falsehood, a myth.

It’s a misnomer that all doctors have bad handwriting.

To use an incorrect, and especially misleading, name for (someone or something); to misidentify, to misname.