A child, or someone remembering being one, describes an evening when the mother's anger fills the house. Her cursing doesn't just echo through the rooms; it "take[s] possession of the heads in the hall." That phrase is odd and a little eerie. "Heads" could mean the people standing there, or it might point to something like portraits or coat hooks, so the anger seems to settle on everything, almost like a haunting.
Against that noise, the speaker and the dog do something small and strange: they "play at theater, dancing." It reads as a way of coping. If you can turn a bad night into a performance, it becomes less frightening. But the last line undercuts the game. They are "hungry for want of dinner," so the play is mixed with real neglect.
The mood is tense and sad, yet oddly tender. The speaker and the dog have each other, and the poem keeps its tone quiet and matter-of-fact, which makes the situation feel even more familiar and bleak.