What does it mean to dream of a boemslung snake?

More information about this particular dream and the specific behavior of the snake would be needed for a reliable interpretation. Generally speaking, dreams of poisonous snakes suggest the dreamer's fear of some unspecified threat. In this case, because the boemslung (Boomslang) is a tree snake, the dreamer might fear some attack from "above," perhaps from supervisors or "higher ups."

... The image of the boomslang might have been drawn from the Harry Potter movies, in which the shed skin is an ingredient in Polyjuice Potion, or from the Marvel Comics' supervillain, Boomslang.