In Mundania witches wear black. Faerie being a reflection witches wear white. Not just styling. White is Structure and Identity. The rule of Law. Science. Civilization. Mundania is White.

Black is Causality and Randomness. The rule of Magic. Faerie is Black. In Mundania witches wear black because they are Chaos in the midst of Order. In Faerie witches wear white because they are Order in the midst of Chaos.

We find out later that the kings of Oz are called Oz and the queens Ozma. Oz is Tir nan Oz, the land of Youth. Ozma is mother of Oz. As the kings of England can be called England and the kings of France can be called France, it makes sense that the kings of Oz can be called Oz. In addition there is the matter of the head of family. The head of family is called mother or father. So we would expect the king of Oz to be called father of Oz.

Mother of Oz is "Oighmamh" //o3'ma:ww// - /ozma:/  (ozma) - "Oighmamh" = "mother of youth" from "Oigh" //o3'// - /oz/ (oz)- "Oigh" = "youth" from "Og" //oc// - /oc/ (oc) - "Og" = "young" combined with "Mamh" //ma:ww// - /ma:/ (ma) - "Mamh" = "mother"

Father of Oz is "Oighathair" //o3'a:har'// - /oza:z/ (ozahz) - "Oighathair" = "father of youth" from "Oigh" //o3'// - /oz/ (oz)- "Oigh" = "youth" from "Og" //oc// - /oc/ (oc) - "Og" = "young" combined with "Athair" //a:har'// - /a:z/ (ahz) - "Athair" = "father"

Since Athair sounds so close to Oigh, I expect that either meaning can be meant when one says Oz and besides Ozaz might sound a bit too much like stuttering.

Then there's that kiss on the forehead that leaves a round shining mark. There are three kinds of homicide among the Ebionites. The mark put on the forehead corresponds to the type. In the Ebionite version of the Hebrew alphabet there are three letters that correspond to Red Mars, the planet of death. For purposeful murderers it is the letter Tav which looks like an X. Such people must live within a village of refuge or go into exile. No one can take vengeance on them but they cannot live within the ordinary community. For negligent homicide it is the letter Shin which looks like a W. No one can take vengeance on them either and they must also live in a village of refuge but on the occasion of the seventh years they may temporarily live with their families. For accidental homicide (recursive homicide in Dorothy's case) where there is no culpability at all it is the letter Ayin which looks like a O. No one may take vengeance on them and they can live anywhere. As a letter of protection against violence, a kiss on the forehead that leaves a round shining mark, it is particularly appropriate.