People have lost their jobs for using the actual world when describing what someone else has said. Context doesn't matter. It's like Voldemort. You simply just aren't allowed to say it alout. Ever.

Retard is a good example actually. For some reason that is forbidden also but imbecile, idiot and moron are fine despite having been used for the exact same purpose historically.

Idiots. —Those so defective that the mental development never exceeds that or a normal child of about two years.

Imbeciles. —Those whose development is higher than that of an idiot, but whose intelligence does not exceed that of a normal child of about seven years.

Morons. —Those whose mental development is above that of an imbecile, but does not exceed that of a normal child of about twelve years.

• Edmund Burke Huey, Backward and Feeble-Minded Children, 1912