Three figures
Elliot's father tells him about the dream he often had. He dreamed of not being able to enter the house, none of the keys he had worked. He looked up and saw three figures standing in a window of a room he didn't know existed. Luc knew that the two of them were his late wife and Miri, the third one he didn't know. He remembers being glad that he could only see silhouettes, because he felt that Lily and Miri weren't the way he knew them. Elliot doesn't tell his father that he had the same dream. The house doesn't want them; it's only interested in women of the family, in generations of carbon copies.
Blood
The imagery of blood appears as a form of familial connection. The main focus of the novel, Miranda, can't shake of the connection to her blood. She can't escape becoming her mother, grandmother, and great-grandmother. "Miranda Silver was not, could not be herself plus all her mothers." She is yearning to be her own person, separate from the blood connection. Another instance of blood being mentioned is in a story Miranda recalls of her GrandAnna. It is a story of a ritual she tried to perform on them when they were little using her own blood. This blood connection is, therefore, present in a metaphorical as well as literal sense.
White
"White is for Witching" is a sentence used in the title, as well as a couple of times in the novel. First when we get a glimpse into Anna's past, her fear of the color white because of its tendency to get dirty to her marriage in white, described as her doing some witching. White is the absence of color. In the novel, it's described as a color for witching because it absorbs all the other colors. Another instance where this sentence is repeated is in a chapter called "Sade", which almost has a form of a children's nursery rhyme, with a sinister message of Sade being unable to defend herself against the evils that lurk inside the house.
