Makeourfuture
It's a definition given in some circumstances and is used to simplify complex arguments that are about specific types of racism, such as group privilege and institutional racism. It's purely stipulative and contextual and does not supercede all other definitions.
Racism at its most basic level is making a pejorative judgement about someone, or treating them less favourably based on their race or ethnicity.
I don't like playing the 'logical fallacy' game, but when the usual suspects on here try to redefine the use of important words like racism and sexism for their own social justice ends, they are giving a persuasive definition and commiting the definist fallacy.
Effectively it's a disingenuous attempt to avoid a point being made against you by 'defining yourself out of the question'.
i.e Labours policy in this instance cannot be racist because you can't be racist against white people.