Normalization
To normalize a form of categorism is to make that categorism perceived as more normal and acceptable.
The normalization may be about a specific focus or a specific facet. Normalization of a foci of categorism can be a matter of outright arguing that the targeted category of people had it coming, doesn't deserve to be protected from harm, or somehow simply doesn't count. Normalization of a facet of categorism can be a matter of downplaying or trivializing the harm this facet of categorism does. To normalize a facet of categorism is often indirectly a matter of normalizing certain foci of categorism, by normalizing facets that are often used against the targeted group.
Classic example: Normalizing violence against women, arguing that women ought to be afraid at all time and accept spousal abuse as well as rape-threats from strangers as their lot in life.