category mistakenoun [ C ]
also category error specializeda mistake in which something is said or believed to be in one category (= group) when in fact it belongs to another:
To treat atheism as a belief system alongside varieties of religious belief is simply a category mistake.
a mistake in which something is said to have a particular quality, or be able to do a particular thing, that only members of another category (= group) of things can have or do:
It is a category mistake to talk about a research programme as being falsified, because only theories can be falsified - research programmes can at most be discredited.