MEME REFERENCE

Is mayonnaise an instrument?

Use for an earnest question that is hilariously off-topic or makes an obvious category error.

What it expresses: Confident participation produces a query showing that the speaker misunderstood the entire subject.
Example: During a discussion of programming languages, someone asks whether Excel counts as a database, and the group uses this reaction.
When not to use it: A beginner asks a relevant foundational question whose answer is not obvious; curiosity alone should not be mocked.