A misnomer is a term or name that mistakenly describes something, often because it suggests something different from what it actually is. It's essentially an incorrect or inaccurate label for something due to misunderstanding or error.
The term «full coverage car insurance» is a bit of misnomer as there is no universal definition of «full coverage.» (good2go.com)
PS: For instance, when Rothko, abstract expressionism is a big misnomer because Rothko was abstract expressionist and DeKooning was RARELY? (rehistoricizing.org)
However, despite best intentions, phrases like «student - led learning» and «students in charge» are actually misnomers for what's happening in these settings. (soundout.org)